256357 has 4 divisors (see below), whose sum is σ = 257580. Its totient is φ = 255136.

The previous prime is 256349. The next prime is 256363. The reversal of 256357 is 753652.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 54756 + 201601 = 234^2 + 449^2 .

It is a cyclic number.

It is not a de Polignac number, because 256357 - 2³ = 256349 is a prime.

It is a super-2 number, since 2×256357² = 131437822898, 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 (256307) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 208 + ... + 745.

It is an arithmetic number, because the mean of its divisors is an integer number (64395).

2²⁵⁶³⁵⁷ is an apocalyptic number.

It is an amenable number.

256357 is a deficient number, since it is larger than the sum of its proper divisors (1223).

256357 is an equidigital number, since it uses as much as digits as its factorization.

256357 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1222.

The product of its digits is 6300, while the sum is 28.

The square root of 256357 is about 506.3170943194. The cubic root of 256357 is about 63.5255441075.

The spelling of 256357 in words is "two hundred fifty-six thousand, three hundred fifty-seven".