21668656624163 has 2 divisors, whose sum is σ = 21668656624164. Its totient is φ = 21668656624162.

The previous prime is 21668656624157. The next prime is 21668656624207. The reversal of 21668656624163 is 36142665686612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21668656624163 - 2⁶ = 21668656624099 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21668656624096 and 21668656624105.

It is not a weakly prime, because it can be changed into another prime (21668656624763) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10834328312081 + 10834328312082.

It is an arithmetic number, because the mean of its divisors is an integer number (10834328312082).

Almost surely, 2^{21668656624163} is an apocalyptic number.

21668656624163 is a deficient number, since it is larger than the sum of its proper divisors (1).

21668656624163 is an equidigital number, since it uses as much as digits as its factorization.

21668656624163 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 89579520, while the sum is 62.

The spelling of 21668656624163 in words is "twenty-one trillion, six hundred sixty-eight billion, six hundred fifty-six million, six hundred twenty-four thousand, one hundred sixty-three".