18691137976 has 64 divisors (see below), whose sum is σ = 42180768000. Its totient is φ = 7585228800.

The previous prime is 18691137973. The next prime is 18691138001. The reversal of 18691137976 is 67973119681.

It is a self number, because there is not a number n which added to its sum of digits gives 18691137976.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18691137973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3890776 + ... + 3895576.

It is an arithmetic number, because the mean of its divisors is an integer number (659074500).

Almost surely, 2^18691137976 is an apocalyptic number.

It is an amenable number.

18691137976 is an abundant number, since it is smaller than the sum of its proper divisors (23489630024).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18691137976 is a wasteful number, since it uses less digits than its factorization.

18691137976 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8492 (or 8488 counting only the distinct ones).

The product of its digits is 3429216, while the sum is 58.

The spelling of 18691137976 in words is "eighteen billion, six hundred ninety-one million, one hundred thirty-seven thousand, nine hundred seventy-six".