640692577718 has 12 divisors (see below), whose sum is σ = 987714894852. Its totient is φ = 311688279720.

The previous prime is 640692577709. The next prime is 640692577739. The reversal of 640692577718 is 817775296046.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 116997368 + ... + 117002843.

It is an arithmetic number, because the mean of its divisors is an integer number (82309574571).

Almost surely, 2^640692577718 is an apocalyptic number.

640692577718 is a deficient number, since it is larger than the sum of its proper divisors (347022317134).

640692577718 is a wasteful number, since it uses less digits than its factorization.

640692577718 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 234000287 (or 234000250 counting only the distinct ones).

The product of its (nonzero) digits is 35562240, while the sum is 62.

The spelling of 640692577718 in words is "six hundred forty billion, six hundred ninety-two million, five hundred seventy-seven thousand, seven hundred eighteen".