25401613665 has 32 divisors (see below), whose sum is σ = 42791685120. Its totient is φ = 12831493824.

The previous prime is 25401613651. The next prime is 25401613669. The reversal of 25401613665 is 56631610452.

It is not a de Polignac number, because 25401613665 - 2⁸ = 25401613409 is a prime.

It is not an unprimeable number, because it can be changed into a prime (25401613669) 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 31 ways as a sum of consecutive naturals, for example, 1698852 + ... + 1713738.

It is an arithmetic number, because the mean of its divisors is an integer number (1337240160).

Almost surely, 2^25401613665 is an apocalyptic number.

It is an amenable number.

25401613665 is a deficient number, since it is larger than the sum of its proper divisors (17390071455).

25401613665 is a wasteful number, since it uses less digits than its factorization.

25401613665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20901.

The product of its (nonzero) digits is 129600, while the sum is 39.

The spelling of 25401613665 in words is "twenty-five billion, four hundred one million, six hundred thirteen thousand, six hundred sixty-five".