18668929 has 2 divisors, whose sum is σ = 18668930. Its totient is φ = 18668928.

The previous prime is 18668921. The next prime is 18668959. The reversal of 18668929 is 92986681.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18490000 + 178929 = 4300^2 + 423^2 .

It is a cyclic number.

It is not a de Polignac number, because 18668929 - 2³ = 18668921 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (18668921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9334464 + 9334465.

It is an arithmetic number, because the mean of its divisors is an integer number (9334465).

Almost surely, 2^18668929 is an apocalyptic number.

It is an amenable number.

18668929 is a deficient number, since it is larger than the sum of its proper divisors (1).

18668929 is an equidigital number, since it uses as much as digits as its factorization.

18668929 is an evil number, because the sum of its binary digits is even.

The product of its digits is 373248, while the sum is 49.

The square root of 18668929 is about 4320.7556052154. The cubic root of 18668929 is about 265.2811967051.

The spelling of 18668929 in words is "eighteen million, six hundred sixty-eight thousand, nine hundred twenty-nine".