639979642162 has 16 divisors (see below), whose sum is σ = 1099457236800. Its totient is φ = 273689669808.

The previous prime is 639979642103. The next prime is 639979642163. The reversal of 639979642162 is 261246979936.

It is a junction number, because it is equal to n+sod(n) for n = 639979642094 and 639979642103.

It is not an unprimeable number, because it can be changed into a prime (639979642163) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48936537 + ... + 48949612.

It is an arithmetic number, because the mean of its divisors is an integer number (68716077300).

Almost surely, 2^639979642162 is an apocalyptic number.

639979642162 is a deficient number, since it is larger than the sum of its proper divisors (459477594638).

639979642162 is a wasteful number, since it uses less digits than its factorization.

639979642162 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97886625.

The product of its digits is 52907904, while the sum is 64.

The spelling of 639979642162 in words is "six hundred thirty-nine billion, nine hundred seventy-nine million, six hundred forty-two thousand, one hundred sixty-two".