26581613 has 2 divisors, whose sum is σ = 26581614. Its totient is φ = 26581612.

The previous prime is 26581609. The next prime is 26581631. The reversal of 26581613 is 31618562.

It is a happy number.

Together with next prime (26581631) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19166884 + 7414729 = 4378^2 + 2723^2 .

It is a cyclic number.

It is not a de Polignac number, because 26581613 - 2² = 26581609 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 26581613.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26581213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13290806 + 13290807.

It is an arithmetic number, because the mean of its divisors is an integer number (13290807).

Almost surely, 2^26581613 is an apocalyptic number.

It is an amenable number.

26581613 is a deficient number, since it is larger than the sum of its proper divisors (1).

26581613 is an equidigital number, since it uses as much as digits as its factorization.

26581613 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8640, while the sum is 32.

The square root of 26581613 is about 5155.7359319500. The cubic root of 26581613 is about 298.4423448845.

The spelling of 26581613 in words is "twenty-six million, five hundred eighty-one thousand, six hundred thirteen".