26666666657 has 2 divisors, whose sum is σ = 26666666658. Its totient is φ = 26666666656.

The previous prime is 26666666651. The next prime is 26666666681. The reversal of 26666666657 is 75666666662.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26652521536 + 14145121 = 163256^2 + 3761^2 .

It is a cyclic number.

It is not a de Polignac number, because 26666666657 - 2⁸ = 26666666401 is a prime.

It is a super-2 number, since 2×26666666657² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 26666666657.

It is not a weakly prime, because it can be changed into another prime (26666666651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13333333328 + 13333333329.

It is an arithmetic number, because the mean of its divisors is an integer number (13333333329).

Almost surely, 2^26666666657 is an apocalyptic number.

It is an amenable number.

26666666657 is a deficient number, since it is larger than the sum of its proper divisors (1).

26666666657 is an equidigital number, since it uses as much as digits as its factorization.

26666666657 is an evil number, because the sum of its binary digits is even.

The product of its digits is 117573120, while the sum is 62.

The spelling of 26666666657 in words is "twenty-six billion, six hundred sixty-six million, six hundred sixty-six thousand, six hundred fifty-seven".