145,721
145,721 is a prime, odd.
145,721 (one hundred forty-five thousand seven hundred twenty-one) is an odd 6-digit number. It is a prime number — divisible only by 1 and itself. Written other ways, in hexadecimal, 0x23939.
Interestingness
Properties
- Parity
- Odd
- Digit count
- 6
- Digit sum
- 20
- Digit product
- 280
- Digital root
- 2
- Palindrome
- No
- Bit width
- 18 bits
- Reversed
- 127,541
- Recamán's sequence
- a(216,974) = 145,721
- Square (n²)
- 21,234,609,841
- Cube (n³)
- 3,094,328,580,640,361
- Divisor count
- 2
- σ(n) — sum of divisors
- 145,722
- φ(n) — Euler's totient
- 145,720
Primality
145,721 is prime. It has exactly two divisors: 1 and itself.
Divisors & multiples
Sums & aliquot sequence
Continued fraction of √n
√145,721 = [381; (1, 2, 1, 3, 4, 1, 6, 152, 1, 1, 4, 1, 5, 6, 1, 4, 1, 29, 1, 2, 2, 3, 1, 2, …)]
Representations
- In words
- one hundred forty-five thousand seven hundred twenty-one
- Ordinal
- 145721st
- Binary
- 100011100100111001
- Octal
- 434471
- Hexadecimal
- 0x23939
- Base64
- Ajk5
- One's complement
- 4,294,821,574 (32-bit)
- Scientific notation
- 1.45721 × 10⁵
- As a duration
- 145,721 s = 1 day, 16 hours, 28 minutes, 41 seconds
As an angle
Historical numeral systems
- Babylonian (base 60)
- 𒌋𒌋𒌋𒌋 𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒁹
- Egyptian hieroglyphic
- 𓆐𓂍𓂍𓂍𓂍𓆼𓆼𓆼𓆼𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓏺
- Greek (Milesian)
- ͵ρμεψκαʹ
- Mayan (base 20)
- 𝋲·𝋤·𝋦·𝋡
- Chinese
- 一十四萬五千七百二十一
- Chinese (financial)
- 壹拾肆萬伍仟柒佰貳拾壹
Also seen as
UTF-8 encoding: F0 A3 A4 B9 (4 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.2.57.57.
- Address
- 0.2.57.57
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.2.57.57
Unspecified address (0.0.0.0/8) — "this network" placeholder.
This number falls in the range of US utility patent numbers. If it's a patent, it would be issued as US 145,721 and was likely granted around 1873.
Patent numbers below 100,000 are excluded as too ambiguous; modern numbering currently reaches roughly 12.5 million.
Related reading
- Prime numbers — The building blocks of arithmetic: what primes are, why they matter, and how we find them.
- Mayan numerals — Vigesimal dots-and-bars with a shell zero — one of the earliest true zeros.