640874160 has 320 divisors, whose sum is σ = 2416988160. Its totient is φ = 155381760.

The previous prime is 640874147. The next prime is 640874173. The reversal of 640874160 is 61478046.

640874160 is a `hidden beast` number, since 640 + 8 + 7 + 4 + 1 + 6 + 0 = 666.

640874160 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (640874147) and next prime (640874173).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1138039 + ... + 1138601.

It is an arithmetic number, because the mean of its divisors is an integer number (7553088).

Almost surely, 2^640874160 is an apocalyptic number.

640874160 is a gapful number since it is divisible by the number (60) 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 640874160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1208494080).

640874160 is an abundant number, since it is smaller than the sum of its proper divisors (1776114000).

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

640874160 is a wasteful number, since it uses less digits than its factorization.

640874160 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 633 (or 621 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 640874160 is about 25315.4924897779. The cubic root of 640874160 is about 862.1660559749.

The spelling of 640874160 in words is "six hundred forty million, eight hundred seventy-four thousand, one hundred sixty".