18919317 has 24 divisors (see below), whose sum is σ = 28092096. Its totient is φ = 11265408.

The previous prime is 18919309. The next prime is 18919361. The reversal of 18919317 is 71391981.

It is not a de Polignac number, because 18919317 - 2³ = 18919309 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18919717) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 148908 + ... + 149034.

It is an arithmetic number, because the mean of its divisors is an integer number (1170504).

Almost surely, 2^18919317 is an apocalyptic number.

18919317 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

18919317 is a deficient number, since it is larger than the sum of its proper divisors (9172779).

18919317 is a wasteful number, since it uses less digits than its factorization.

18919317 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 297 (or 170 counting only the distinct ones).

The product of its digits is 13608, while the sum is 39.

The square root of 18919317 is about 4349.6341225441. The cubic root of 18919317 is about 266.4619190496.

The spelling of 18919317 in words is "eighteen million, nine hundred nineteen thousand, three hundred seventeen".