25640270815 has 4 divisors (see below), whose sum is σ = 30768324984. Its totient is φ = 20512216648.

The previous prime is 25640270797. The next prime is 25640270827. The reversal of 25640270815 is 51807204652.

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 25640270815 - 2⁵ = 25640270783 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2564027077 + ... + 2564027086.

It is an arithmetic number, because the mean of its divisors is an integer number (7692081246).

Almost surely, 2^25640270815 is an apocalyptic number.

25640270815 is a deficient number, since it is larger than the sum of its proper divisors (5128054169).

25640270815 is an equidigital number, since it uses as much as digits as its factorization.

25640270815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5128054168.

The product of its (nonzero) digits is 134400, while the sum is 40.

The spelling of 25640270815 in words is "twenty-five billion, six hundred forty million, two hundred seventy thousand, eight hundred fifteen".