639244942 has 16 divisors (see below), whose sum is σ = 1097573472. Its totient is φ = 273530880.

The previous prime is 639244919. The next prime is 639244951. The reversal of 639244942 is 249442936.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26643 + ... + 44590.

It is an arithmetic number, because the mean of its divisors is an integer number (68598342).

Almost surely, 2^639244942 is an apocalyptic number.

639244942 is a deficient number, since it is larger than the sum of its proper divisors (458328530).

639244942 is a wasteful number, since it uses less digits than its factorization.

639244942 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71883.

The product of its digits is 373248, while the sum is 43.

The square root of 639244942 is about 25283.2937332144. The cubic root of 639244942 is about 861.4348419936.

The spelling of 639244942 in words is "six hundred thirty-nine million, two hundred forty-four thousand, nine hundred forty-two".