18390900 has 72 divisors (see below), whose sum is σ = 58058784. Its totient is φ = 4457600.

The previous prime is 18390899. The next prime is 18390929. The reversal of 18390900 is 909381.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 514 + ... + 6086.

It is an arithmetic number, because the mean of its divisors is an integer number (806372).

Almost surely, 2^18390900 is an apocalyptic number.

18390900 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 18390900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29029392).

18390900 is an abundant number, since it is smaller than the sum of its proper divisors (39667884).

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

18390900 is a wasteful number, since it uses less digits than its factorization.

18390900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5601 (or 5594 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 30.

The square root of 18390900 is about 4288.4612625043. The cubic root of 18390900 is about 263.9576952414.

The spelling of 18390900 in words is "eighteen million, three hundred ninety thousand, nine hundred".