18538490 has 16 divisors (see below), whose sum is σ = 35125920. Its totient is φ = 7025040.

The previous prime is 18538489. The next prime is 18538523. The reversal of 18538490 is 9483581.

It is a super-2 number, since 2×18538490² = 687351222960200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48596 + ... + 48975.

It is an arithmetic number, because the mean of its divisors is an integer number (2195370).

Almost surely, 2^18538490 is an apocalyptic number.

18538490 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18538490 is a deficient number, since it is larger than the sum of its proper divisors (16587430).

18538490 is a wasteful number, since it uses less digits than its factorization.

18538490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97597.

The product of its (nonzero) digits is 34560, while the sum is 38.

The square root of 18538490 is about 4305.6346802765. The cubic root of 18538490 is about 264.6619160772.

The spelling of 18538490 in words is "eighteen million, five hundred thirty-eight thousand, four hundred ninety".