18198172494 has 24 divisors (see below), whose sum is σ = 39434795400. Its totient is φ = 6065223408.

The previous prime is 18198172483. The next prime is 18198172501. The reversal of 18198172494 is 49427189181.

18198172494 is a `hidden beast` number, since 1 + 8 + 1 + 9 + 81 + 72 + 494 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 18198172494.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 72924 + ... + 204240.

It is an arithmetic number, because the mean of its divisors is an integer number (1643116475).

Almost surely, 2^18198172494 is an apocalyptic number.

18198172494 is an abundant number, since it is smaller than the sum of its proper divisors (21236622906).

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

18198172494 is a wasteful number, since it uses less digits than its factorization.

18198172494 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139024 (or 139021 counting only the distinct ones).

The product of its digits is 1161216, while the sum is 54.

The spelling of 18198172494 in words is "eighteen billion, one hundred ninety-eight million, one hundred seventy-two thousand, four hundred ninety-four".