26664295681 has 2 divisors, whose sum is σ = 26664295682. Its totient is φ = 26664295680.

The previous prime is 26664295649. The next prime is 26664295733. The reversal of 26664295681 is 18659246662.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21874410000 + 4789885681 = 147900^2 + 69209^2 .

It is a cyclic number.

It is not a de Polignac number, because 26664295681 - 2⁵ = 26664295649 is a prime.

It is a super-2 number, since 2×26664295681² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (26664295181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13332147840 + 13332147841.

It is an arithmetic number, because the mean of its divisors is an integer number (13332147841).

Almost surely, 2^26664295681 is an apocalyptic number.

It is an amenable number.

26664295681 is a deficient number, since it is larger than the sum of its proper divisors (1).

26664295681 is an equidigital number, since it uses as much as digits as its factorization.

26664295681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7464960, while the sum is 55.

The spelling of 26664295681 in words is "twenty-six billion, six hundred sixty-four million, two hundred ninety-five thousand, six hundred eighty-one".