18989217 has 24 divisors (see below), whose sum is σ = 29829800. Its totient is φ = 11570688.

The previous prime is 18989213. The next prime is 18989219. The reversal of 18989217 is 71298981.

It can be written as a sum of positive squares in 4 ways, for example, as 404496 + 18584721 = 636^2 + 4311^2 .

It is not a de Polignac number, because 18989217 - 2² = 18989213 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18989213) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12009 + ... + 13497.

Almost surely, 2^18989217 is an apocalyptic number.

It is an amenable number.

18989217 is a deficient number, since it is larger than the sum of its proper divisors (10840583).

18989217 is a wasteful number, since it uses less digits than its factorization.

18989217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1617 (or 1614 counting only the distinct ones).

The product of its digits is 72576, while the sum is 45.

The square root of 18989217 is about 4357.6618730691. The cubic root of 18989217 is about 266.7896757145.

The spelling of 18989217 in words is "eighteen million, nine hundred eighty-nine thousand, two hundred seventeen".