256745 has 4 divisors (see below), whose sum is σ = 308100. Its totient is φ = 205392.

The previous prime is 256723. The next prime is 256757. The reversal of 256745 is 547652.

256745 is nontrivially palindromic in base 15.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 52441 + 204304 = 229^2 + 452^2 .

It is a cyclic number.

It is not a de Polignac number, because 256745 - 2⁸ = 256489 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25670 + ... + 25679.

It is an arithmetic number, because the mean of its divisors is an integer number (77025).

2²⁵⁶⁷⁴⁵ is an apocalyptic number.

It is an amenable number.

256745 is a deficient number, since it is larger than the sum of its proper divisors (51355).

256745 is an equidigital number, since it uses as much as digits as its factorization.

256745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51354.

The product of its digits is 8400, while the sum is 29.

The square root of 256745 is about 506.7001085455. The cubic root of 256745 is about 63.5575768932.

It can be divided in two parts, 256 and 745, that added together give a palindrome (1001).

The spelling of 256745 in words is "two hundred fifty-six thousand, seven hundred forty-five".