642726790 has 16 divisors (see below), whose sum is σ = 1173204000. Its totient is φ = 253469440.

The previous prime is 642726787. The next prime is 642726827. The reversal of 642726790 is 97627246.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 451915 + ... + 453334.

It is an arithmetic number, because the mean of its divisors is an integer number (73325250).

Almost surely, 2^642726790 is an apocalyptic number.

642726790 is a deficient number, since it is larger than the sum of its proper divisors (530477210).

642726790 is a wasteful number, since it uses less digits than its factorization.

642726790 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 905327.

The product of its (nonzero) digits is 254016, while the sum is 43.

The square root of 642726790 is about 25352.0569185224. The cubic root of 642726790 is about 862.9960358891.

The spelling of 642726790 in words is "six hundred forty-two million, seven hundred twenty-six thousand, seven hundred ninety".