20917179 has 12 divisors (see below), whose sum is σ = 30332016. Its totient is φ = 13890192.

The previous prime is 20917159. The next prime is 20917181. The reversal of 20917179 is 97171902.

It is not a de Polignac number, because 20917179 - 2⁸ = 20916923 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20917129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2052 + ... + 6785.

It is an arithmetic number, because the mean of its divisors is an integer number (2527668).

Almost surely, 2^20917179 is an apocalyptic number.

20917179 is a deficient number, since it is larger than the sum of its proper divisors (9414837).

20917179 is a wasteful number, since it uses less digits than its factorization.

20917179 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9106 (or 9103 counting only the distinct ones).

The product of its (nonzero) digits is 7938, while the sum is 36.

The square root of 20917179 is about 4573.5302557215. The cubic root of 20917179 is about 275.5292463597.

The spelling of 20917179 in words is "twenty million, nine hundred seventeen thousand, one hundred seventy-nine".