642431786 has 32 divisors (see below), whose sum is σ = 1015676928. Its totient is φ = 304380720.

The previous prime is 642431773. The next prime is 642431813. The reversal of 642431786 is 687134246.

642431786 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 653051 + ... + 654033.

It is an arithmetic number, because the mean of its divisors is an integer number (31739904).

Almost surely, 2^642431786 is an apocalyptic number.

642431786 is a deficient number, since it is larger than the sum of its proper divisors (373245142).

642431786 is a wasteful number, since it uses less digits than its factorization.

642431786 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1226.

The product of its digits is 193536, while the sum is 41.

The square root of 642431786 is about 25346.2381035135. The cubic root of 642431786 is about 862.8639806897.

The spelling of 642431786 in words is "six hundred forty-two million, four hundred thirty-one thousand, seven hundred eighty-six".