639979642102 has 32 divisors (see below), whose sum is σ = 1028567030400. Its totient is φ = 297735854400.

The previous prime is 639979642091. The next prime is 639979642103. The reversal of 639979642102 is 201246979936.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639979642103) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2315202 + ... + 2576842.

It is an arithmetic number, because the mean of its divisors is an integer number (32142719700).

Almost surely, 2^639979642102 is an apocalyptic number.

639979642102 is a deficient number, since it is larger than the sum of its proper divisors (388587388298).

639979642102 is a wasteful number, since it uses less digits than its factorization.

639979642102 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262812.

The product of its (nonzero) digits is 8817984, while the sum is 58.

The spelling of 639979642102 in words is "six hundred thirty-nine billion, nine hundred seventy-nine million, six hundred forty-two thousand, one hundred two".