26402043581 has 2 divisors, whose sum is σ = 26402043582. Its totient is φ = 26402043580.

The previous prime is 26402043509. The next prime is 26402043583. The reversal of 26402043581 is 18534020462.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 26224887481 + 177156100 = 161941^2 + 13310^2 .

It is a cyclic number.

It is not a de Polignac number, because 26402043581 - 2¹⁸ = 26401781437 is a prime.

It is a super-2 number, since 2×26402043581² (a number of 22 digits) contains 22 as substring.

It is a Sophie Germain prime.

Together with 26402043583, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26402043583) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13201021790 + 13201021791.

It is an arithmetic number, because the mean of its divisors is an integer number (13201021791).

Almost surely, 2^26402043581 is an apocalyptic number.

It is an amenable number.

26402043581 is a deficient number, since it is larger than the sum of its proper divisors (1).

26402043581 is an equidigital number, since it uses as much as digits as its factorization.

26402043581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 46080, while the sum is 35.

The spelling of 26402043581 in words is "twenty-six billion, four hundred two million, forty-three thousand, five hundred eighty-one".