18120800 has 36 divisors (see below), whose sum is σ = 44239356. Its totient is φ = 7248000.

The previous prime is 18120799. The next prime is 18120829. The reversal of 18120800 is 802181.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 10526 + ... + 12125.

It is an arithmetic number, because the mean of its divisors is an integer number (1228871).

Almost surely, 2^18120800 is an apocalyptic number.

18120800 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18120800 is an abundant number, since it is smaller than the sum of its proper divisors (26118556).

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

18120800 is a wasteful number, since it uses less digits than its factorization.

18120800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22671 (or 22658 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 20.

The square root of 18120800 is about 4256.8532979185. The cubic root of 18120800 is about 262.6591023386.

Adding to 18120800 its reverse (802181), we get a palindrome (18922981).

The spelling of 18120800 in words is "eighteen million, one hundred twenty thousand, eight hundred".