18918900 has 432 divisors, whose sum is σ = 83119680. Its totient is φ = 3628800.

The previous prime is 18918883. The next prime is 18918919. The reversal of 18918900 is 981981.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 1455294 + ... + 1455306.

Almost surely, 2^18918900 is an apocalyptic number.

18918900 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18918900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41559840).

18918900 is an abundant number, since it is smaller than the sum of its proper divisors (64200780).

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

18918900 is a wasteful number, since it uses less digits than its factorization.

18918900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61 (or 41 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 36.

The square root of 18918900 is about 4349.5861872137. The cubic root of 18918900 is about 266.4599613426.

18918900 divided by its sum of digits (36) gives a palindrome (525525).

It can be divided in two parts, 189 and 18900, that multiplied together give a square (3572100 = 1890²).

The spelling of 18918900 in words is "eighteen million, nine hundred eighteen thousand, nine hundred".