20868163 has 4 divisors (see below), whose sum is σ = 22095720. Its totient is φ = 19640608.

The previous prime is 20868157. The next prime is 20868181. The reversal of 20868163 is 36186802.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 36186802 = 2 ⋅18093401.

It is a cyclic number.

It is not a de Polignac number, because 20868163 - 2⁵ = 20868131 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20868193) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 613753 + ... + 613786.

It is an arithmetic number, because the mean of its divisors is an integer number (5523930).

Almost surely, 2^20868163 is an apocalyptic number.

20868163 is a deficient number, since it is larger than the sum of its proper divisors (1227557).

20868163 is a wasteful number, since it uses less digits than its factorization.

20868163 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1227556.

The product of its (nonzero) digits is 13824, while the sum is 34.

The square root of 20868163 is about 4568.1684513599. The cubic root of 20868163 is about 275.3138587352.

The spelling of 20868163 in words is "twenty million, eight hundred sixty-eight thousand, one hundred sixty-three".