18390072100 has 81 divisors (see below), whose sum is σ = 40689463633. Its totient is φ = 7214452000.

The previous prime is 18390072079. The next prime is 18390072109. The reversal of 18390072100 is 127009381.

The square root of 18390072100 is 135610.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 6620425956 + 11769646144 = 81366^2 + 108488^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18390072109) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 96283005 + ... + 96283195.

Almost surely, 2^18390072100 is an apocalyptic number.

18390072100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18390072100 is the 135610-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18390072100

18390072100 is an abundant number, since it is smaller than the sum of its proper divisors (22299391533).

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

18390072100 is an equidigital number, since it uses as much as digits as its factorization.

18390072100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 538 (or 269 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 31.

The spelling of 18390072100 in words is "eighteen billion, three hundred ninety million, seventy-two thousand, one hundred".