26396135561 has 2 divisors, whose sum is σ = 26396135562. Its totient is φ = 26396135560.

The previous prime is 26396135551. The next prime is 26396135599. The reversal of 26396135561 is 16553169362.

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., 26310462025 + 85673536 = 162205^2 + 9256^2 .

It is a cyclic number.

It is not a de Polignac number, because 26396135561 - 2⁶ = 26396135497 is a prime.

It is not a weakly prime, because it can be changed into another prime (26396135551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13198067780 + 13198067781.

It is an arithmetic number, because the mean of its divisors is an integer number (13198067781).

Almost surely, 2^26396135561 is an apocalyptic number.

It is an amenable number.

26396135561 is a deficient number, since it is larger than the sum of its proper divisors (1).

26396135561 is an equidigital number, since it uses as much as digits as its factorization.

26396135561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 874800, while the sum is 47.

The spelling of 26396135561 in words is "twenty-six billion, three hundred ninety-six million, one hundred thirty-five thousand, five hundred sixty-one".