18932397172 has 18 divisors (see below), whose sum is σ = 35682157014. Its totient is φ = 8737571520.

The previous prime is 18932397139. The next prime is 18932397179. The reversal of 18932397172 is 27179323981.

It can be written as a sum of positive squares in 3 ways, for example, as 511392996 + 18421004176 = 22614^2 + 135724^2 .

It is a Harshad number since it is a multiple of its sum of digits (52).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18932397179) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 982672 + ... + 1001752.

Almost surely, 2^18932397172 is an apocalyptic number.

It is an amenable number.

18932397172 is a deficient number, since it is larger than the sum of its proper divisors (16749759842).

18932397172 is an frugal number, since it uses more digits than its factorization.

18932397172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38179 (or 19096 counting only the distinct ones).

The product of its digits is 1143072, while the sum is 52.

Multiplying 18932397172 by its sum of digits (52), we get a square (984484652944 = 992212²).

18932397172 divided by its sum of digits (52) gives a square (364084561 = 19081²).

The spelling of 18932397172 in words is "eighteen billion, nine hundred thirty-two million, three hundred ninety-seven thousand, one hundred seventy-two".