18909190 has 16 divisors (see below), whose sum is σ = 34504128. Its totient is φ = 7459776.

The previous prime is 18909173. The next prime is 18909221. The reversal of 18909190 is 9190981.

It is a super-2 number, since 2×18909190² = 715114932912200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12222 + ... + 13681.

It is an arithmetic number, because the mean of its divisors is an integer number (2156508).

Almost surely, 2^18909190 is an apocalyptic number.

18909190 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18909190 is a deficient number, since it is larger than the sum of its proper divisors (15594938).

18909190 is a wasteful number, since it uses less digits than its factorization.

18909190 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25983.

The product of its (nonzero) digits is 5832, while the sum is 37.

The square root of 18909190 is about 4348.4698458193. The cubic root of 18909190 is about 266.4143672719.

The spelling of 18909190 in words is "eighteen million, nine hundred nine thousand, one hundred ninety".