18899969 has 16 divisors (see below), whose sum is σ = 21288960. Its totient is φ = 16631760.

The previous prime is 18899941. The next prime is 18899977. The reversal of 18899969 is 96999881.

It is a cyclic number.

It is not a de Polignac number, because 18899969 - 2¹² = 18895873 is a prime.

It is a super-2 number, since 2×18899969² = 714417656401922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18899929) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 71732 + ... + 71994.

It is an arithmetic number, because the mean of its divisors is an integer number (1330560).

Almost surely, 2^18899969 is an apocalyptic number.

It is an amenable number.

18899969 is a deficient number, since it is larger than the sum of its proper divisors (2388991).

18899969 is a wasteful number, since it uses less digits than its factorization.

18899969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 460.

The product of its digits is 2519424, while the sum is 59.

The square root of 18899969 is about 4347.4094585166. The cubic root of 18899969 is about 266.3710548877.

The spelling of 18899969 in words is "eighteen million, eight hundred ninety-nine thousand, nine hundred sixty-nine".