26216721931 has 2 divisors, whose sum is σ = 26216721932. Its totient is φ = 26216721930.

The previous prime is 26216721907. The next prime is 26216721967. The reversal of 26216721931 is 13912761262.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 26216721931 - 2¹⁷ = 26216590859 is a prime.

It is a super-2 number, since 2×26216721931² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (26216721991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13108360965 + 13108360966.

It is an arithmetic number, because the mean of its divisors is an integer number (13108360966).

Almost surely, 2^26216721931 is an apocalyptic number.

26216721931 is a deficient number, since it is larger than the sum of its proper divisors (1).

26216721931 is an equidigital number, since it uses as much as digits as its factorization.

26216721931 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 54432, while the sum is 40.

The spelling of 26216721931 in words is "twenty-six billion, two hundred sixteen million, seven hundred twenty-one thousand, nine hundred thirty-one".