21296117917 has 2 divisors, whose sum is σ = 21296117918. Its totient is φ = 21296117916.

The previous prime is 21296117867. The next prime is 21296117963. The reversal of 21296117917 is 71971169212.

It is an a-pointer prime, because the next prime (21296117963) can be obtained adding 21296117917 to its sum of digits (46).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21171996036 + 124121881 = 145506^2 + 11141^2 .

It is a cyclic number.

It is not a de Polignac number, because 21296117917 - 2⁷ = 21296117789 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21296117977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10648058958 + 10648058959.

It is an arithmetic number, because the mean of its divisors is an integer number (10648058959).

Almost surely, 2^21296117917 is an apocalyptic number.

It is an amenable number.

21296117917 is a deficient number, since it is larger than the sum of its proper divisors (1).

21296117917 is an equidigital number, since it uses as much as digits as its factorization.

21296117917 is an evil number, because the sum of its binary digits is even.

The product of its digits is 95256, while the sum is 46.

The spelling of 21296117917 in words is "twenty-one billion, two hundred ninety-six million, one hundred seventeen thousand, nine hundred seventeen".