18669997 has 12 divisors (see below), whose sum is σ = 20206620. Its totient is φ = 17228288.

The previous prime is 18669979. The next prime is 18670007. The reversal of 18669997 is 79996681.

It can be written as a sum of positive squares in 2 ways, for example, as 8003241 + 10666756 = 2829^2 + 3266^2 .

It is a de Polignac number, because none of the positive numbers 2^k-18669997 is a prime.

It is a super-3 number, since 3×18669997³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18669907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 14733 + ... + 15949.

It is an arithmetic number, because the mean of its divisors is an integer number (1683885).

Almost surely, 2^18669997 is an apocalyptic number.

It is an amenable number.

18669997 is a deficient number, since it is larger than the sum of its proper divisors (1536623).

18669997 is a wasteful number, since it uses less digits than its factorization.

18669997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1292 (or 1269 counting only the distinct ones).

The product of its digits is 1469664, while the sum is 55.

The square root of 18669997 is about 4320.8791929421. The cubic root of 18669997 is about 265.2862552870.

The spelling of 18669997 in words is "eighteen million, six hundred sixty-nine thousand, nine hundred ninety-seven".