18807209972 has 6 divisors (see below), whose sum is σ = 32912617458. Its totient is φ = 9403604984.

The previous prime is 18807209959. The next prime is 18807210077. The reversal of 18807209972 is 27990270881.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 12598715536 + 6208494436 = 112244^2 + 78794^2 .

It is a super-2 number, since 2×18807209972² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2350901243 + ... + 2350901250.

It is an arithmetic number, because the mean of its divisors is an integer number (5485436243).

Almost surely, 2^18807209972 is an apocalyptic number.

It is an amenable number.

18807209972 is a deficient number, since it is larger than the sum of its proper divisors (14105407486).

18807209972 is a wasteful number, since it uses less digits than its factorization.

18807209972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4701802497 (or 4701802495 counting only the distinct ones).

The product of its (nonzero) digits is 1016064, while the sum is 53.

The spelling of 18807209972 in words is "eighteen billion, eight hundred seven million, two hundred nine thousand, nine hundred seventy-two".