21706117165169 has 2 divisors, whose sum is σ = 21706117165170. Its totient is φ = 21706117165168.

The previous prime is 21706117165147. The next prime is 21706117165189. The reversal of 21706117165169 is 96156171160712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20246580144400 + 1459537020769 = 4499620^2 + 1208113^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21706117165169 is a prime.

It is a super-2 number, since 2×21706117165169² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21706117165169.

It is not a weakly prime, because it can be changed into another prime (21706117165189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10853058582584 + 10853058582585.

It is an arithmetic number, because the mean of its divisors is an integer number (10853058582585).

Almost surely, 2^{21706117165169} is an apocalyptic number.

It is an amenable number.

21706117165169 is a deficient number, since it is larger than the sum of its proper divisors (1).

21706117165169 is an equidigital number, since it uses as much as digits as its factorization.

21706117165169 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 952560, while the sum is 53.

The spelling of 21706117165169 in words is "twenty-one trillion, seven hundred six billion, one hundred seventeen million, one hundred sixty-five thousand, one hundred sixty-nine".