25613406664 has 8 divisors (see below), whose sum is σ = 48025137510. Its totient is φ = 12806703328.

The previous prime is 25613406661. The next prime is 25613406667. The reversal of 25613406664 is 46660431652.

It is an interprime number because it is at equal distance from previous prime (25613406661) and next prime (25613406667).

It can be written as a sum of positive squares in only one way, i.e., 21535562500 + 4077844164 = 146750^2 + 63858^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 25613406664.

It is not an unprimeable number, because it can be changed into a prime (25613406661) 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 as a sum of consecutive naturals, namely, 1600837909 + ... + 1600837924.

Almost surely, 2^25613406664 is an apocalyptic number.

It is an amenable number.

25613406664 is a deficient number, since it is larger than the sum of its proper divisors (22411730846).

25613406664 is a wasteful number, since it uses less digits than its factorization.

25613406664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3201675839 (or 3201675835 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 43.

The spelling of 25613406664 in words is "twenty-five billion, six hundred thirteen million, four hundred six thousand, six hundred sixty-four".