18198020 has 12 divisors (see below), whose sum is σ = 38215884. Its totient is φ = 7279200.

The previous prime is 18198017. The next prime is 18198053. The reversal of 18198020 is 2089181.

It can be written as a sum of positive squares in 2 ways, for example, as 1827904 + 16370116 = 1352^2 + 4046^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 454931 + ... + 454970.

It is an arithmetic number, because the mean of its divisors is an integer number (3184657).

Almost surely, 2^18198020 is an apocalyptic number.

18198020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18198020 is an abundant number, since it is smaller than the sum of its proper divisors (20017864).

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

18198020 is a wasteful number, since it uses less digits than its factorization.

18198020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 909910 (or 909908 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 29.

The square root of 18198020 is about 4265.9137356491. The cubic root of 18198020 is about 263.0316722255.

The spelling of 18198020 in words is "eighteen million, one hundred ninety-eight thousand, twenty".