256440729600 has 1632 divisors, whose sum is σ = 1123393812480. Its totient is φ = 56623104000.

The previous prime is 256440729593. The next prime is 256440729679. The reversal of 256440729600 is 6927044652.

256440729600 is a `hidden beast` number, since 2 + 56 + 440 + 72 + 96 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1632).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 8272281585 + ... + 8272281615.

Almost surely, 2^256440729600 is an apocalyptic number.

256440729600 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 256440729600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (561696906240).

256440729600 is an abundant number, since it is smaller than the sum of its proper divisors (866953082880).

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

256440729600 is a wasteful number, since it uses less digits than its factorization.

256440729600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110 (or 69 counting only the distinct ones).

The product of its (nonzero) digits is 725760, while the sum is 45.

The spelling of 256440729600 in words is "two hundred fifty-six billion, four hundred forty million, seven hundred twenty-nine thousand, six hundred".