26311921891 has 2 divisors, whose sum is σ = 26311921892. Its totient is φ = 26311921890.

The previous prime is 26311921873. The next prime is 26311921901. The reversal of 26311921891 is 19812911362.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 26311921891 - 2²⁵ = 26278367459 is a prime.

It is the 162210-th Hogben number.

It is not a weakly prime, because it can be changed into another prime (26311921861) by changing a digit.

It is a nontrivial repunit in base 162209.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13155960945 + 13155960946.

It is an arithmetic number, because the mean of its divisors is an integer number (13155960946).

Almost surely, 2^26311921891 is an apocalyptic number.

26311921891 is a deficient number, since it is larger than the sum of its proper divisors (1).

26311921891 is an equidigital number, since it uses as much as digits as its factorization.

26311921891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46656, while the sum is 43.

The spelling of 26311921891 in words is "twenty-six billion, three hundred eleven million, nine hundred twenty-one thousand, eight hundred ninety-one".