18921172024 has 16 divisors (see below), whose sum is σ = 35904634920. Its totient is φ = 9346602720.

The previous prime is 18921171979. The next prime is 18921172027. The reversal of 18921172024 is 42027112981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18921172027) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14247207 + ... + 14248534.

Almost surely, 2^18921172024 is an apocalyptic number.

It is an amenable number.

18921172024 is a deficient number, since it is larger than the sum of its proper divisors (16983462896).

18921172024 is a wasteful number, since it uses less digits than its factorization.

18921172024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28495830 (or 28495826 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 37.

The spelling of 18921172024 in words is "eighteen billion, nine hundred twenty-one million, one hundred seventy-two thousand, twenty-four".