257987751840 has 1536 divisors, whose sum is σ = 1158312960000. Its totient is φ = 53274267648.

The previous prime is 257987751839. The next prime is 257987751863. The reversal of 257987751840 is 48157789752.

257987751840 is a `hidden beast` number, since 2 + 5 + 7 + 9 + 8 + 77 + 518 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 1136509807 + ... + 1136510033.

It is an arithmetic number, because the mean of its divisors is an integer number (754110000).

Almost surely, 2^257987751840 is an apocalyptic number.

257987751840 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 257987751840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (579156480000).

257987751840 is an abundant number, since it is smaller than the sum of its proper divisors (900325208160).

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

257987751840 is a wasteful number, since it uses less digits than its factorization.

257987751840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 344 (or 316 counting only the distinct ones).

The product of its (nonzero) digits is 39513600, while the sum is 63.

The spelling of 257987751840 in words is "two hundred fifty-seven billion, nine hundred eighty-seven million, seven hundred fifty-one thousand, eight hundred forty".