26540015581 has 2 divisors, whose sum is σ = 26540015582. Its totient is φ = 26540015580.

The previous prime is 26540015539. The next prime is 26540015587. The reversal of 26540015581 is 18551004562.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 26357522500 + 182493081 = 162350^2 + 13509^2 .

It is a cyclic number.

It is not a de Polignac number, because 26540015581 - 2¹⁵ = 26539982813 is a prime.

It is a super-2 number, since 2×26540015581² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 26540015581.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26540015587) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13270007790 + 13270007791.

It is an arithmetic number, because the mean of its divisors is an integer number (13270007791).

Almost surely, 2^26540015581 is an apocalyptic number.

It is an amenable number.

26540015581 is a deficient number, since it is larger than the sum of its proper divisors (1).

26540015581 is an equidigital number, since it uses as much as digits as its factorization.

26540015581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48000, while the sum is 37.

The spelling of 26540015581 in words is "twenty-six billion, five hundred forty million, fifteen thousand, five hundred eighty-one".