26791777021 has 2 divisors, whose sum is σ = 26791777022. Its totient is φ = 26791777020.

The previous prime is 26791776989. The next prime is 26791777027. The reversal of 26791777021 is 12077719762.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 26679628921 + 112148100 = 163339^2 + 10590^2 .

It is a cyclic number.

It is not a de Polignac number, because 26791777021 - 2⁵ = 26791776989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26791777027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13395888510 + 13395888511.

It is an arithmetic number, because the mean of its divisors is an integer number (13395888511).

Almost surely, 2^26791777021 is an apocalyptic number.

It is an amenable number.

26791777021 is a deficient number, since it is larger than the sum of its proper divisors (1).

26791777021 is an equidigital number, since it uses as much as digits as its factorization.

26791777021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 518616, while the sum is 49.

The spelling of 26791777021 in words is "twenty-six billion, seven hundred ninety-one million, seven hundred seventy-seven thousand, twenty-one".