642863790 has 48 divisors (see below), whose sum is σ = 1733357808. Its totient is φ = 171429696.

The previous prime is 642863783. The next prime is 642863827. The reversal of 642863790 is 97368246.

642863790 is a `hidden beast` number, since 6 + 4 + 2 + 8 + 637 + 9 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 129847 + ... + 134706.

It is an arithmetic number, because the mean of its divisors is an integer number (36111621).

Almost surely, 2^642863790 is an apocalyptic number.

642863790 is an abundant number, since it is smaller than the sum of its proper divisors (1090494018).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

642863790 is a wasteful number, since it uses less digits than its factorization.

642863790 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 264575 (or 264563 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 45.

The square root of 642863790 is about 25354.7587249416. The cubic root of 642863790 is about 863.0573486477.

The spelling of 642863790 in words is "six hundred forty-two million, eight hundred sixty-three thousand, seven hundred ninety".