25605645601 has 4 divisors (see below), whose sum is σ = 25606637892. Its totient is φ = 25604653312.

The previous prime is 25605645589. The next prime is 25605645623. The reversal of 25605645601 is 10654650652.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13284867600 + 12320778001 = 115260^2 + 110999^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25605645601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25605645641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 456376 + ... + 509401.

It is an arithmetic number, because the mean of its divisors is an integer number (6401659473).

Almost surely, 2^25605645601 is an apocalyptic number.

It is an amenable number.

25605645601 is a deficient number, since it is larger than the sum of its proper divisors (992291).

25605645601 is an equidigital number, since it uses as much as digits as its factorization.

25605645601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 992290.

The product of its (nonzero) digits is 216000, while the sum is 40.

The spelling of 25605645601 in words is "twenty-five billion, six hundred five million, six hundred forty-five thousand, six hundred one".