640157328 has 60 divisors (see below), whose sum is σ = 1794581568. Its totient is φ = 213024960.

The previous prime is 640157311. The next prime is 640157351. The reversal of 640157328 is 823751046.

640157328 is a `hidden beast` number, since 64 + 0 + 1 + 573 + 28 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 640157292 and 640157301.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 89733 + ... + 96603.

Almost surely, 2^640157328 is an apocalyptic number.

It is an amenable number.

640157328 is an abundant number, since it is smaller than the sum of its proper divisors (1154424240).

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

640157328 is a wasteful number, since it uses less digits than its factorization.

640157328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7532 (or 7523 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The square root of 640157328 is about 25301.3305578975. The cubic root of 640157328 is about 861.8444854149.

The spelling of 640157328 in words is "six hundred forty million, one hundred fifty-seven thousand, three hundred twenty-eight".