26604128557 has 2 divisors, whose sum is σ = 26604128558. Its totient is φ = 26604128556.

The previous prime is 26604128501. The next prime is 26604128647. The reversal of 26604128557 is 75582140662.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14414643721 + 12189484836 = 120061^2 + 110406^2 .

It is a cyclic number.

It is not a de Polignac number, because 26604128557 - 2¹¹ = 26604126509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26604128857) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13302064278 + 13302064279.

It is an arithmetic number, because the mean of its divisors is an integer number (13302064279).

Almost surely, 2^26604128557 is an apocalyptic number.

It is an amenable number.

26604128557 is a deficient number, since it is larger than the sum of its proper divisors (1).

26604128557 is an equidigital number, since it uses as much as digits as its factorization.

26604128557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 806400, while the sum is 46.

The spelling of 26604128557 in words is "twenty-six billion, six hundred four million, one hundred twenty-eight thousand, five hundred fifty-seven".