26561623519 has 2 divisors, whose sum is σ = 26561623520. Its totient is φ = 26561623518.

The previous prime is 26561623493. The next prime is 26561623549. The reversal of 26561623519 is 91532616562.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 26561623519 - 2¹⁹ = 26561099231 is a prime.

It is a super-2 number, since 2×26561623519² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26561623549) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13280811759 + 13280811760.

It is an arithmetic number, because the mean of its divisors is an integer number (13280811760).

Almost surely, 2^26561623519 is an apocalyptic number.

26561623519 is a deficient number, since it is larger than the sum of its proper divisors (1).

26561623519 is an equidigital number, since it uses as much as digits as its factorization.

26561623519 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 583200, while the sum is 46.

The spelling of 26561623519 in words is "twenty-six billion, five hundred sixty-one million, six hundred twenty-three thousand, five hundred nineteen".