18973390988 has 24 divisors (see below), whose sum is σ = 33368176800. Its totient is φ = 9439714688.

The previous prime is 18973390967. The next prime is 18973391011. The reversal of 18973390988 is 88909337981.

It is a super-2 number, since 2×18973390988² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 892256 + ... + 913272.

It is an arithmetic number, because the mean of its divisors is an integer number (1390340700).

Almost surely, 2^18973390988 is an apocalyptic number.

It is an amenable number.

18973390988 is a deficient number, since it is larger than the sum of its proper divisors (14394785812).

18973390988 is a wasteful number, since it uses less digits than its factorization.

18973390988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22129 (or 22127 counting only the distinct ones).

The product of its (nonzero) digits is 23514624, while the sum is 65.

The spelling of 18973390988 in words is "eighteen billion, nine hundred seventy-three million, three hundred ninety thousand, nine hundred eighty-eight".