640975532 has 6 divisors (see below), whose sum is σ = 1121707188. Its totient is φ = 320487764.

The previous prime is 640975453. The next prime is 640975537. The reversal of 640975532 is 235579046.

It is a self number, because there is not a number n which added to its sum of digits gives 640975532.

It is not an unprimeable number, because it can be changed into a prime (640975537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80121938 + ... + 80121945.

It is an arithmetic number, because the mean of its divisors is an integer number (186951198).

Almost surely, 2^640975532 is an apocalyptic number.

It is an amenable number.

640975532 is a deficient number, since it is larger than the sum of its proper divisors (480731656).

640975532 is a wasteful number, since it uses less digits than its factorization.

640975532 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160243887 (or 160243885 counting only the distinct ones).

The product of its (nonzero) digits is 226800, while the sum is 41.

The square root of 640975532 is about 25317.4945837853. The cubic root of 640975532 is about 862.2115120593.

The spelling of 640975532 in words is "six hundred forty million, nine hundred seventy-five thousand, five hundred thirty-two".