25664360491 has 12 divisors (see below), whose sum is σ = 32568502680. Its totient is φ = 19998202560.

The previous prime is 25664360443. The next prime is 25664360509. The reversal of 25664360491 is 19406346652.

It is not a de Polignac number, because 25664360491 - 2¹¹ = 25664358443 is a prime.

It is a super-2 number, since 2×25664360491² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (25664360441) 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 in 11 ways as a sum of consecutive naturals, for example, 23806846 + ... + 23807923.

It is an arithmetic number, because the mean of its divisors is an integer number (2714041890).

Almost surely, 2^25664360491 is an apocalyptic number.

25664360491 is a deficient number, since it is larger than the sum of its proper divisors (6904142189).

25664360491 is a wasteful number, since it uses less digits than its factorization.

25664360491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47614794 (or 47614787 counting only the distinct ones).

The product of its (nonzero) digits is 933120, while the sum is 46.

The spelling of 25664360491 in words is "twenty-five billion, six hundred sixty-four million, three hundred sixty thousand, four hundred ninety-one".