640452188 has 48 divisors (see below), whose sum is σ = 1181537280. Its totient is φ = 303388800.

The previous prime is 640452151. The next prime is 640452193. The reversal of 640452188 is 881254046.

It is a happy number.

It is a super-2 number, since 2×640452188² = 820358010227974688, which contains 22 as substring.

It is a congruent number.

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, 1445495 + ... + 1445937.

It is an arithmetic number, because the mean of its divisors is an integer number (24615360).

Almost surely, 2^640452188 is an apocalyptic number.

It is an amenable number.

640452188 is a deficient number, since it is larger than the sum of its proper divisors (541085092).

640452188 is a wasteful number, since it uses less digits than its factorization.

640452188 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 698 (or 696 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 38.

The square root of 640452188 is about 25307.1568533488. The cubic root of 640452188 is about 861.9767885467.

The spelling of 640452188 in words is "six hundred forty million, four hundred fifty-two thousand, one hundred eighty-eight".