26281640657 has 4 divisors (see below), whose sum is σ = 26341508160. Its totient is φ = 26221773156.

The previous prime is 26281640597. The next prime is 26281640677. The reversal of 26281640657 is 75604618262.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 26281640657 - 2⁸ = 26281640401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (26281640677) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29933093 + ... + 29933970.

It is an arithmetic number, because the mean of its divisors is an integer number (6585377040).

Almost surely, 2^26281640657 is an apocalyptic number.

It is an amenable number.

26281640657 is a deficient number, since it is larger than the sum of its proper divisors (59867503).

26281640657 is an equidigital number, since it uses as much as digits as its factorization.

26281640657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59867502.

The product of its (nonzero) digits is 967680, while the sum is 47.

The spelling of 26281640657 in words is "twenty-six billion, two hundred eighty-one million, six hundred forty thousand, six hundred fifty-seven".