20931163 has 4 divisors (see below), whose sum is σ = 22834008. Its totient is φ = 19028320.

The previous prime is 20931151. The next prime is 20931187. The reversal of 20931163 is 36113902.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20931163 is a prime.

It is a super-2 number, since 2×20931163² = 876227169065138, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20931133) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 951406 + ... + 951427.

It is an arithmetic number, because the mean of its divisors is an integer number (5708502).

Almost surely, 2^20931163 is an apocalyptic number.

20931163 is a deficient number, since it is larger than the sum of its proper divisors (1902845).

20931163 is a wasteful number, since it uses less digits than its factorization.

20931163 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1902844.

The product of its (nonzero) digits is 972, while the sum is 25.

The square root of 20931163 is about 4575.0587974364. The cubic root of 20931163 is about 275.5906335838.

The spelling of 20931163 in words is "twenty million, nine hundred thirty-one thousand, one hundred sixty-three".