18981198 has 24 divisors (see below), whose sum is σ = 41348736. Its totient is φ = 6292800.

The previous prime is 18981191. The next prime is 18981199. The reversal of 18981198 is 89118981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18981191) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 678 + ... + 6198.

It is an arithmetic number, because the mean of its divisors is an integer number (1722864).

Almost surely, 2^18981198 is an apocalyptic number.

18981198 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

18981198 is an abundant number, since it is smaller than the sum of its proper divisors (22367538).

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

18981198 is a wasteful number, since it uses less digits than its factorization.

18981198 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5720 (or 5717 counting only the distinct ones).

The product of its digits is 41472, while the sum is 45.

The square root of 18981198 is about 4356.7416723969. The cubic root of 18981198 is about 266.7521160189.

The spelling of 18981198 in words is "eighteen million, nine hundred eighty-one thousand, one hundred ninety-eight".