21259166713 has 2 divisors, whose sum is σ = 21259166714. Its totient is φ = 21259166712.

The previous prime is 21259166711. The next prime is 21259166717. The reversal of 21259166713 is 31766195212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18717796969 + 2541369744 = 136813^2 + 50412^2 .

It is a cyclic number.

It is not a de Polignac number, because 21259166713 - 2¹ = 21259166711 is a prime.

It is a super-2 number, since 2×21259166713² (a number of 21 digits) contains 22 as substring.

Together with 21259166711, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21259166713.

It is not a weakly prime, because it can be changed into another prime (21259166711) 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, 10629583356 + 10629583357.

It is an arithmetic number, because the mean of its divisors is an integer number (10629583357).

Almost surely, 2^21259166713 is an apocalyptic number.

It is an amenable number.

21259166713 is a deficient number, since it is larger than the sum of its proper divisors (1).

21259166713 is an equidigital number, since it uses as much as digits as its factorization.

21259166713 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 136080, while the sum is 43.

The spelling of 21259166713 in words is "twenty-one billion, two hundred fifty-nine million, one hundred sixty-six thousand, seven hundred thirteen".