256394040 has 64 divisors (see below), whose sum is σ = 879068160. Its totient is φ = 58604160.

The previous prime is 256394023. The next prime is 256394057. The reversal of 256394040 is 40493652.

It is an interprime number because it is at equal distance from previous prime (256394023) and next prime (256394057).

It is a junction number, because it is equal to n+sod(n) for n = 256393992 and 256394010.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 151776 + ... + 153455.

It is an arithmetic number, because the mean of its divisors is an integer number (13735440).

Almost surely, 2^256394040 is an apocalyptic number.

256394040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256394040 is an abundant number, since it is smaller than the sum of its proper divisors (622674120).

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

256394040 is a wasteful number, since it uses less digits than its factorization.

256394040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 305252 (or 305248 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 33.

The square root of 256394040 is about 16012.3090152545. The cubic root of 256394040 is about 635.2860347757.

It can be divided in two parts, 2563940 and 40, that added together give a triangular number (2563980 = T₂₂₆₄).

The spelling of 256394040 in words is "two hundred fifty-six million, three hundred ninety-four thousand, forty".