26515764661 has 2 divisors, whose sum is σ = 26515764662. Its totient is φ = 26515764660.

The previous prime is 26515764631. The next prime is 26515764707. The reversal of 26515764661 is 16646751562.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22931347761 + 3584416900 = 151431^2 + 59870^2 .

It is a cyclic number.

It is not a de Polignac number, because 26515764661 - 2¹³ = 26515756469 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26515764631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13257882330 + 13257882331.

It is an arithmetic number, because the mean of its divisors is an integer number (13257882331).

Almost surely, 2^26515764661 is an apocalyptic number.

It is an amenable number.

26515764661 is a deficient number, since it is larger than the sum of its proper divisors (1).

26515764661 is an equidigital number, since it uses as much as digits as its factorization.

26515764661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1814400, while the sum is 49.

The spelling of 26515764661 in words is "twenty-six billion, five hundred fifteen million, seven hundred sixty-four thousand, six hundred sixty-one".