256465940 has 48 divisors (see below), whose sum is σ = 551205648. Its totient is φ = 100199424.

The previous prime is 256465931. The next prime is 256465943. The reversal of 256465940 is 49564652.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 75724804 + 180741136 = 8702^2 + 13444^2 .

It is a Smith number, since the sum of its digits (41) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256465943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 331394 + ... + 332166.

It is an arithmetic number, because the mean of its divisors is an integer number (11483451).

Almost surely, 2^256465940 is an apocalyptic number.

256465940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256465940 is an abundant number, since it is smaller than the sum of its proper divisors (294739708).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

256465940 is a wasteful number, since it uses less digits than its factorization.

256465940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1148 (or 1146 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 41.

The square root of 256465940 is about 16014.5540056537. The cubic root of 256465940 is about 635.3454131670.

The spelling of 256465940 in words is "two hundred fifty-six million, four hundred sixty-five thousand, nine hundred forty".