18972416117 has 4 divisors (see below), whose sum is σ = 18978047616. Its totient is φ = 18966784620.

The previous prime is 18972416083. The next prime is 18972416149. The reversal of 18972416117 is 71161427981.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18972416117 - 2⁶ = 18972416053 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18972416417) 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, 2810693 + ... + 2817434.

It is an arithmetic number, because the mean of its divisors is an integer number (4744511904).

Almost surely, 2^18972416117 is an apocalyptic number.

It is an amenable number.

18972416117 is a deficient number, since it is larger than the sum of its proper divisors (5631499).

18972416117 is an equidigital number, since it uses as much as digits as its factorization.

18972416117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5631498.

The product of its digits is 169344, while the sum is 47.

The spelling of 18972416117 in words is "eighteen billion, nine hundred seventy-two million, four hundred sixteen thousand, one hundred seventeen".