256472440 has 32 divisors (see below), whose sum is σ = 659501280. Its totient is φ = 87933312.

The previous prime is 256472413. The next prime is 256472497. The reversal of 256472440 is 44274652.

It is a super-2 number, since 2×256472440² = 131556224959107200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 256472396 and 256472405.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 457707 + ... + 458266.

It is an arithmetic number, because the mean of its divisors is an integer number (20609415).

Almost surely, 2^256472440 is an apocalyptic number.

256472440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256472440 is an abundant number, since it is smaller than the sum of its proper divisors (403028840).

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

256472440 is a wasteful number, since it uses less digits than its factorization.

256472440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 915991 (or 915987 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 34.

The square root of 256472440 is about 16014.7569447682. The cubic root of 256472440 is about 635.3507806247.

The spelling of 256472440 in words is "two hundred fifty-six million, four hundred seventy-two thousand, four hundred forty".