18912090 has 48 divisors (see below), whose sum is σ = 46546272. Its totient is φ = 4916736.

The previous prime is 18912083. The next prime is 18912107. The reversal of 18912090 is 9021981.

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 194922 + ... + 195018.

It is an arithmetic number, because the mean of its divisors is an integer number (969714).

Almost surely, 2^18912090 is an apocalyptic number.

18912090 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 18912090, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23273136).

18912090 is an abundant number, since it is smaller than the sum of its proper divisors (27634182).

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

18912090 is an equidigital number, since it uses as much as digits as its factorization.

18912090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271 (or 174 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 30.

The square root of 18912090 is about 4348.8032836632. The cubic root of 18912090 is about 266.4279860849.

The spelling of 18912090 in words is "eighteen million, nine hundred twelve thousand, ninety".