18908117 has 2 divisors, whose sum is σ = 18908118. Its totient is φ = 18908116.

The previous prime is 18908111. The next prime is 18908119. The reversal of 18908117 is 71180981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9991921 + 8916196 = 3161^2 + 2986^2 .

It is a cyclic number.

It is not a de Polignac number, because 18908117 - 2¹² = 18904021 is a prime.

Together with 18908119, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18908111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9454058 + 9454059.

It is an arithmetic number, because the mean of its divisors is an integer number (9454059).

Almost surely, 2^18908117 is an apocalyptic number.

It is an amenable number.

18908117 is a deficient number, since it is larger than the sum of its proper divisors (1).

18908117 is an equidigital number, since it uses as much as digits as its factorization.

18908117 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4032, while the sum is 35.

The square root of 18908117 is about 4348.3464673368. The cubic root of 18908117 is about 266.4093279581.

The spelling of 18908117 in words is "eighteen million, nine hundred eight thousand, one hundred seventeen".