640751524 has 48 divisors (see below), whose sum is σ = 1335398400. Its totient is φ = 263227680.

The previous prime is 640751519. The next prime is 640751537. The reversal of 640751524 is 425157046.

It is a self number, because there is not a number n which added to its sum of digits gives 640751524.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 89427 + ... + 96325.

It is an arithmetic number, because the mean of its divisors is an integer number (27820800).

Almost surely, 2^640751524 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 640751524, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (667699200).

640751524 is an abundant number, since it is smaller than the sum of its proper divisors (694646876).

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

640751524 is a wasteful number, since it uses less digits than its factorization.

640751524 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7048 (or 7046 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 34.

The square root of 640751524 is about 25313.0702207377. The cubic root of 640751524 is about 862.1110585209. Note that the first 3 decimals are identical.

The spelling of 640751524 in words is "six hundred forty million, seven hundred fifty-one thousand, five hundred twenty-four".