18289917 has 6 divisors (see below), whose sum is σ = 26418782. Its totient is φ = 12193272.

The previous prime is 18289903. The next prime is 18289927. The reversal of 18289917 is 71998281.

It can be written as a sum of positive squares in only one way, i.e., 14333796 + 3956121 = 3786^2 + 1989^2 .

It is a de Polignac number, because none of the positive numbers 2^k-18289917 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18289927) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1016098 + ... + 1016115.

Almost surely, 2^18289917 is an apocalyptic number.

It is an amenable number.

18289917 is a deficient number, since it is larger than the sum of its proper divisors (8128865).

18289917 is a wasteful number, since it uses less digits than its factorization.

18289917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2032219 (or 2032216 counting only the distinct ones).

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

The square root of 18289917 is about 4276.6712522709. The cubic root of 18289917 is about 263.4736845515.

The spelling of 18289917 in words is "eighteen million, two hundred eighty-nine thousand, nine hundred seventeen".