640613564 has 6 divisors (see below), whose sum is σ = 1121073744. Its totient is φ = 320306780.

The previous prime is 640613539. The next prime is 640613569. The reversal of 640613564 is 465316046.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640613569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80076692 + ... + 80076699.

It is an arithmetic number, because the mean of its divisors is an integer number (186845624).

Almost surely, 2^640613564 is an apocalyptic number.

It is an amenable number.

640613564 is a deficient number, since it is larger than the sum of its proper divisors (480460180).

640613564 is a wasteful number, since it uses less digits than its factorization.

640613564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160153395 (or 160153393 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 35.

The square root of 640613564 is about 25310.3449996242. The cubic root of 640613564 is about 862.0491804636.

The spelling of 640613564 in words is "six hundred forty million, six hundred thirteen thousand, five hundred sixty-four".