256490 has 16 divisors (see below), whose sum is σ = 497448. Its totient is φ = 94656.

The previous prime is 256489. The next prime is 256493. The reversal of 256490 is 94652.

It can be written as a sum of positive squares in 4 ways, for example, as 121801 + 134689 = 349^2 + 367^2 .

It is a Harshad number since it is a multiple of its sum of digits (26).

It is not an unprimeable number, because it can be changed into a prime (256493) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 857 + ... + 1116.

2²⁵⁶⁴⁹⁰ is an apocalyptic number.

256490 is a deficient number, since it is larger than the sum of its proper divisors (240958).

256490 is a wasteful number, since it uses less digits than its factorization.

256490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1993.

The product of its (nonzero) digits is 2160, while the sum is 26.

The square root of 256490 is about 506.4484179065. The cubic root of 256490 is about 63.5365280565.

The spelling of 256490 in words is "two hundred fifty-six thousand, four hundred ninety".