642751751524 has 9 divisors (see below), whose sum is σ = 1124818371187. Its totient is φ = 321375074044.

The previous prime is 642751751491. The next prime is 642751751531. The reversal of 642751751524 is 425157157246.

The square root of 642751751524 is 801718.

It is a perfect power (a square), and thus also a powerful number.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 1403007 + ... + 1803865.

Almost surely, 2^642751751524 is an apocalyptic number.

642751751524 is the 801718-th square number.

It is an amenable number.

642751751524 is a deficient number, since it is larger than the sum of its proper divisors (482066619663).

642751751524 is an frugal number, since it uses more digits than its factorization.

642751751524 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 801722 (or 400861 counting only the distinct ones).

The product of its digits is 2352000, while the sum is 49.

Multiplying 642751751524 by its sum of digits (49), we get a square (31494835824676 = 5612026²).

The spelling of 642751751524 in words is "six hundred forty-two billion, seven hundred fifty-one million, seven hundred fifty-one thousand, five hundred twenty-four".