21336996844729 has 2 divisors, whose sum is σ = 21336996844730. Its totient is φ = 21336996844728.

The previous prime is 21336996844687. The next prime is 21336996844907. The reversal of 21336996844729 is 92744869963312.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15742825804729 + 5594171040000 = 3967723^2 + 2365200^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21336996844729 is a prime.

It is not a weakly prime, because it can be changed into another prime (21336996845729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10668498422364 + 10668498422365.

It is an arithmetic number, because the mean of its divisors is an integer number (10668498422365).

Almost surely, 2^{21336996844729} is an apocalyptic number.

It is an amenable number.

21336996844729 is a deficient number, since it is larger than the sum of its proper divisors (1).

21336996844729 is an equidigital number, since it uses as much as digits as its factorization.

21336996844729 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 846526464, while the sum is 73.

The spelling of 21336996844729 in words is "twenty-one trillion, three hundred thirty-six billion, nine hundred ninety-six million, eight hundred forty-four thousand, seven hundred twenty-nine".