20886161 has 2 divisors, whose sum is σ = 20886162. Its totient is φ = 20886160.

The previous prime is 20886143. The next prime is 20886163. The reversal of 20886161 is 16168802.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19855936 + 1030225 = 4456^2 + 1015^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20886161 is a prime.

It is a super-3 number, since 3×20886161³ (a number of 23 digits) contains 333 as substring.

Together with 20886163, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20886163) 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 as a sum of consecutive naturals, namely, 10443080 + 10443081.

It is an arithmetic number, because the mean of its divisors is an integer number (10443081).

Almost surely, 2^20886161 is an apocalyptic number.

It is an amenable number.

20886161 is a deficient number, since it is larger than the sum of its proper divisors (1).

20886161 is an equidigital number, since it uses as much as digits as its factorization.

20886161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4608, while the sum is 32.

The square root of 20886161 is about 4570.1379629066. The cubic root of 20886161 is about 275.3929852494.

The spelling of 20886161 in words is "twenty million, eight hundred eighty-six thousand, one hundred sixty-one".