18020900 has 36 divisors (see below), whose sum is σ = 39299568. Its totient is φ = 7172640.

The previous prime is 18020897. The next prime is 18020909. The reversal of 18020900 is 902081.

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

It is not an unprimeable number, because it can be changed into a prime (18020909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30407 + ... + 30993.

Almost surely, 2^18020900 is an apocalyptic number.

18020900 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18020900 is an abundant number, since it is smaller than the sum of its proper divisors (21278668).

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

18020900 is a wasteful number, since it uses less digits than its factorization.

18020900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 908 (or 901 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 18020900 is about 4245.1030611753. The cubic root of 18020900 is about 262.1755325865.

Adding to 18020900 its reverse (902081), we get a palindrome (18922981).

The spelling of 18020900 in words is "eighteen million, twenty thousand, nine hundred".