26640507265 has 4 divisors (see below), whose sum is σ = 31968608724. Its totient is φ = 21312405808.

The previous prime is 26640507211. The next prime is 26640507277. The reversal of 26640507265 is 56270504662.

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 16822868209 + 9817639056 = 129703^2 + 99084^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-26640507265 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2664050722 + ... + 2664050731.

It is an arithmetic number, because the mean of its divisors is an integer number (7992152181).

Almost surely, 2^26640507265 is an apocalyptic number.

It is an amenable number.

26640507265 is a deficient number, since it is larger than the sum of its proper divisors (5328101459).

26640507265 is an equidigital number, since it uses as much as digits as its factorization.

26640507265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5328101458.

The product of its (nonzero) digits is 604800, while the sum is 43.

The spelling of 26640507265 in words is "twenty-six billion, six hundred forty million, five hundred seven thousand, two hundred sixty-five".