25642436635 has 4 divisors (see below), whose sum is σ = 30770923968. Its totient is φ = 20513949304.

The previous prime is 25642436629. The next prime is 25642436639. The reversal of 25642436635 is 53663424652.

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

It is a cyclic number.

It is not a de Polignac number, because 25642436635 - 2⁷ = 25642436507 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25642436639) 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, 2564243659 + ... + 2564243668.

It is an arithmetic number, because the mean of its divisors is an integer number (7692730992).

Almost surely, 2^25642436635 is an apocalyptic number.

25642436635 is a deficient number, since it is larger than the sum of its proper divisors (5128487333).

25642436635 is an equidigital number, since it uses as much as digits as its factorization.

25642436635 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5128487332.

The product of its digits is 3110400, while the sum is 46.

The spelling of 25642436635 in words is "twenty-five billion, six hundred forty-two million, four hundred thirty-six thousand, six hundred thirty-five".