18161204172 has 48 divisors (see below), whose sum is σ = 43566765312. Its totient is φ = 5883986880.

The previous prime is 18161204141. The next prime is 18161204177. The reversal of 18161204172 is 27140216181.

It is not an unprimeable number, because it can be changed into a prime (18161204177) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 415647 + ... + 457257.

It is an arithmetic number, because the mean of its divisors is an integer number (907640944).

Almost surely, 2^18161204172 is an apocalyptic number.

18161204172 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

18161204172 is an abundant number, since it is smaller than the sum of its proper divisors (25405561140).

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

18161204172 is a wasteful number, since it uses less digits than its factorization.

18161204172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42638 (or 42636 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 33.

The spelling of 18161204172 in words is "eighteen billion, one hundred sixty-one million, two hundred four thousand, one hundred seventy-two".