21996826717 has 2 divisors, whose sum is σ = 21996826718. Its totient is φ = 21996826716.

The previous prime is 21996826697. The next prime is 21996826721. The reversal of 21996826717 is 71762869912.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16319807001 + 5677019716 = 127749^2 + 75346^2 .

It is a cyclic number.

It is not a de Polignac number, because 21996826717 - 2³¹ = 19849343069 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21996826727) 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, 10998413358 + 10998413359.

It is an arithmetic number, because the mean of its divisors is an integer number (10998413359).

Almost surely, 2^21996826717 is an apocalyptic number.

It is an amenable number.

21996826717 is a deficient number, since it is larger than the sum of its proper divisors (1).

21996826717 is an equidigital number, since it uses as much as digits as its factorization.

21996826717 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4572288, while the sum is 58.

The spelling of 21996826717 in words is "twenty-one billion, nine hundred ninety-six million, eight hundred twenty-six thousand, seven hundred seventeen".