257656548240 has 2400 divisors, whose sum is σ = 1225694764800. Its totient is φ = 48910417920.

The previous prime is 257656548223. The next prime is 257656548251. The reversal of 257656548240 is 42845656752.

257656548240 is a `hidden beast` number, since 2 + 5 + 7 + 6 + 56 + 548 + 2 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 479 ways as a sum of consecutive naturals, for example, 4223877810 + ... + 4223877870.

It is an arithmetic number, because the mean of its divisors is an integer number (510706152).

Almost surely, 2^257656548240 is an apocalyptic number.

257656548240 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 257656548240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (612847382400).

257656548240 is an abundant number, since it is smaller than the sum of its proper divisors (968038216560).

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

257656548240 is a wasteful number, since it uses less digits than its factorization.

257656548240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167 (or 139 counting only the distinct ones).

The product of its (nonzero) digits is 16128000, while the sum is 54.

The spelling of 257656548240 in words is "two hundred fifty-seven billion, six hundred fifty-six million, five hundred forty-eight thousand, two hundred forty".