256081357 has 4 divisors (see below), whose sum is σ = 292664416. Its totient is φ = 219498300.

The previous prime is 256081349. The next prime is 256081361. The reversal of 256081357 is 753180652.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 256081357 - 2³ = 256081349 is a prime.

It is a super-2 number, since 2×256081357² = 131155322805922898, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256081327) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18291519 + ... + 18291532.

It is an arithmetic number, because the mean of its divisors is an integer number (73166104).

Almost surely, 2^256081357 is an apocalyptic number.

It is an amenable number.

256081357 is a deficient number, since it is larger than the sum of its proper divisors (36583059).

256081357 is an equidigital number, since it uses as much as digits as its factorization.

256081357 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36583058.

The product of its (nonzero) digits is 50400, while the sum is 37.

The square root of 256081357 is about 16002.5422042874. The cubic root of 256081357 is about 635.0276773023.

The spelling of 256081357 in words is "two hundred fifty-six million, eighty-one thousand, three hundred fifty-seven".