26643320249969 has 2 divisors, whose sum is σ = 26643320249970. Its totient is φ = 26643320249968.

The previous prime is 26643320249921. The next prime is 26643320249971. The reversal of 26643320249969 is 96994202334662.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23056322890000 + 3586997359969 = 4801700^2 + 1893937^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-26643320249969 is a prime.

It is a super-2 number, since 2×26643320249969² (a number of 28 digits) contains 22 as substring.

Together with 26643320249971, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (26643320249999) 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, 13321660124984 + 13321660124985.

It is an arithmetic number, because the mean of its divisors is an integer number (13321660124985).

Almost surely, 2^{26643320249969} is an apocalyptic number.

It is an amenable number.

26643320249969 is a deficient number, since it is larger than the sum of its proper divisors (1).

26643320249969 is an equidigital number, since it uses as much as digits as its factorization.

26643320249969 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 181398528, while the sum is 65.

The spelling of 26643320249969 in words is "twenty-six trillion, six hundred forty-three billion, three hundred twenty million, two hundred forty-nine thousand, nine hundred sixty-nine".