638969969836 has 24 divisors (see below), whose sum is σ = 1219912344000. Its totient is φ = 290426470800.

The previous prime is 638969969831. The next prime is 638969969887.

638969969836 is nontrivially palindromic in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 638969969836.

It is not an unprimeable number, because it can be changed into a prime (638969969831) 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, 561915 + ... + 1262413.

It is an arithmetic number, because the mean of its divisors is an integer number (50829681000).

Almost surely, 2^638969969836 is an apocalyptic number.

It is an amenable number.

638969969836 is a deficient number, since it is larger than the sum of its proper divisors (580942374164).

638969969836 is a wasteful number, since it uses less digits than its factorization.

638969969836 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 721245 (or 721243 counting only the distinct ones).

The product of its digits is 4897760256, while the sum is 82.

The spelling of 638969969836 in words is "six hundred thirty-eight billion, nine hundred sixty-nine million, nine hundred sixty-nine thousand, eight hundred thirty-six".