18989290 has 16 divisors (see below), whose sum is σ = 34502112. Its totient is φ = 7524304.

The previous prime is 18989249. The next prime is 18989291. The reversal of 18989290 is 9298981.

It is a happy number.

It is an alternating number because its digits alternate between odd and even.

It is a self number, because there is not a number n which added to its sum of digits gives 18989290.

It is not an unprimeable number, because it can be changed into a prime (18989291) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7804 + ... + 9943.

It is an arithmetic number, because the mean of its divisors is an integer number (2156382).

Almost surely, 2^18989290 is an apocalyptic number.

18989290 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18989290 is a deficient number, since it is larger than the sum of its proper divisors (15512822).

18989290 is a wasteful number, since it uses less digits than its factorization.

18989290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17861.

The product of its (nonzero) digits is 93312, while the sum is 46.

The square root of 18989290 is about 4357.6702491125. The cubic root of 18989290 is about 266.7900175860.

The spelling of 18989290 in words is "eighteen million, nine hundred eighty-nine thousand, two hundred ninety".