25664644653391 has 2 divisors, whose sum is σ = 25664644653392. Its totient is φ = 25664644653390.

The previous prime is 25664644653371. The next prime is 25664644653491. The reversal of 25664644653391 is 19335644646652.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25664644653391 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25664644653301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12832322326695 + 12832322326696.

It is an arithmetic number, because the mean of its divisors is an integer number (12832322326696).

Almost surely, 2^{25664644653391} is an apocalyptic number.

25664644653391 is a deficient number, since it is larger than the sum of its proper divisors (1).

25664644653391 is an equidigital number, since it uses as much as digits as its factorization.

25664644653391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 335923200, while the sum is 64.

The spelling of 25664644653391 in words is "twenty-five trillion, six hundred sixty-four billion, six hundred forty-four million, six hundred fifty-three thousand, three hundred ninety-one".