Number

70

70 is a composite number, even, a calendar year.

Abundant Number Arithmetic Number Happy Number Harshad / Niven Odious Number Pell Number Pentagonal Pernicious Number Recamán's Sequence Sphenic Number Squarefree Weird Number Year

Notable events — 70 AD

Sep 8 Roman forces under Titus sack Jerusalem and destroy the Second Temple.

Events compiled from Wikipedia ↗ · Licensed CC BY-SA 4.0

Historical context — 70 BC

Calendar year

Year 70 BC was a year of the pre-Julian Roman calendar.

Excerpt from Wikipedia (en) ↗ · Licensed CC BY-SA 4.0 · English fallback Read the full article on Wikipedia →

Year facts

Year type: Common year
Standard 365-day year; not divisible by 4 (or divisible by 100 but not 400).
Days in year: 365
ISO weeks: 52
Started on: Wednesday
January 1, 70
Ended on: Wednesday
December 31, 70
Friday the 13ths: 1
One Friday the 13th this year.
Decade: 70s
70–79
Century: 1st century
1–100
Millennium: 1st millennium
1–1000
Years ago: 1,956
1956 years before 2026.

In other calendars

Hebrew: 3830 / 3831 AM
Rosh Hashanah falls in September/October.
Chinese: Year of the zodiac:Metal zodiac:Horse
Sexagenary cycle position 7 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 613 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Ethiopian: 62 / 63 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): -8 / -9 Saka
Indian national calendar; year starts in March.

Cultural significance

Christian sacred

Jesus sent out seventy disciples; the seventy nations of the world in Jewish tradition.

Luke 10:1; Genesis 10.

Sourced from Wikipedia (Numerology, Chinese numerology, Gematria, and per-culture articles).

Properties

Parity: Even
Digit count: 2
Digit sum: 7
Digit product: 0
Digital root: 7
Palindrome: No
Bit width: 7 bits
Reversed: 7
Recamán's sequence: a(87) = 70
Square (n²): 4,900
Cube (n³): 343,000
Divisor count: 8
σ(n) — sum of divisors: 144
φ(n) — Euler's totient: 24
Sum of prime factors: 14

Primality

Prime factorization: 2 × 5 × 7

Nearest primes: 67 (−3) · 71 (+1)

Divisors & multiples

All divisors (8)

1 · 2 · 5 · 7 · 10 · 14 · 35 (half) · 70

Aliquot sum (sum of proper divisors): 74

Factor pairs (a × b = 70)

1 × 70

2 × 35

5 × 14

7 × 10

First multiples

70 · 140 (double) · 210 · 280 · 350 · 420 · 490 · 560 · 630 · 700

Sums & aliquot sequence

As consecutive integers: 16 + 17 + 18 + 19 12 + 13 + 14 + 15 + 16 7 + 8 + … + 13

Aliquot sequence: 70 → 74 → 40 → 50 → 43 → 1 → 0 — terminates at zero

Representations

In words: seventy
Ordinal: 70th
Roman numeral: LXX
Binary: 1000110
Octal: 106
Hexadecimal: 0x46
Base64: Rg==
One's complement: 185 (8-bit)

In other bases

ternary (3) 2121

quaternary (4) 1012

quinary (5) 240

senary (6) 154

septenary (7) 130

nonary (9) 77

undecimal (11) 64

duodecimal (12) 5a

tridecimal (13) 55

tetradecimal (14) 50

pentadecimal (15) 4a

Historical numeral systems

Babylonian (base 60): 𒁹 𒌋
Egyptian hieroglyphic: 𓎆𓎆𓎆𓎆𓎆𓎆𓎆
Greek (Milesian): οʹ
Mayan (base 20): 𝋣·𝋪
Chinese: 七十
Chinese (financial): 柒拾

In other modern scripts

Eastern Arabic ٧٠ Devanagari ७० Bengali ৭০ Tamil ௭௦ Thai ๗๐ Tibetan ༧༠ Khmer ៧០ Lao ໗໐ Burmese ၇၀

Digit at this position in famous constants

π — Pi (π): Digit 70 = 6
e — Euler's number (e): Digit 70 = 6
φ — Golden ratio (φ): Digit 70 = 0
√2 — Pythagoras's (√2): Digit 70 = 2
ln 2 — Natural log of 2: Digit 70 = 3
γ — Euler-Mascheroni (γ): Digit 70 = 7

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 70, here are decompositions:

3 + 67 = 70
11 + 59 = 70
17 + 53 = 70
23 + 47 = 70
29 + 41 = 70

ASCII character

As an ASCII codepoint, 70 is F. Printable ASCII character F.

Hex color

#000046

RGB(0, 0, 70)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.0.70.

Address: 0.0.0.70
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.0.70

Unspecified address (0.0.0.0/8) — "this network" placeholder.

US numbered highway

Matches numbered highway designation:

I-70 — Cove Fort, UT to Baltimore, MD.

Interstate 70 on Wikipedia ↗