26511551257 has 4 divisors (see below), whose sum is σ = 27906896080. Its totient is φ = 25116206436.

The previous prime is 26511551201. The next prime is 26511551299. The reversal of 26511551257 is 75215511562.

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 a de Polignac number, because none of the positive numbers 2^k-26511551257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (26511051257) 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, 697672383 + ... + 697672420.

It is an arithmetic number, because the mean of its divisors is an integer number (6976724020).

Almost surely, 2^26511551257 is an apocalyptic number.

It is an amenable number.

26511551257 is a deficient number, since it is larger than the sum of its proper divisors (1395344823).

26511551257 is a wasteful number, since it uses less digits than its factorization.

26511551257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1395344822.

The product of its digits is 105000, while the sum is 40.

The spelling of 26511551257 in words is "twenty-six billion, five hundred eleven million, five hundred fifty-one thousand, two hundred fifty-seven".