13365581 has 2 divisors, whose sum is σ = 13365582. Its totient is φ = 13365580.

The previous prime is 13365577. The next prime is 13365623. The reversal of 13365581 is 18556331.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12888100 + 477481 = 3590^2 + 691^2 .

It is a cyclic number.

It is not a de Polignac number, because 13365581 - 2² = 13365577 is a prime.

It is a super-2 number, since 2×13365581² = 357277510935122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13365571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6682790 + 6682791.

It is an arithmetic number, because the mean of its divisors is an integer number (6682791).

Almost surely, 2^13365581 is an apocalyptic number.

It is an amenable number.

13365581 is a deficient number, since it is larger than the sum of its proper divisors (1).

13365581 is an equidigital number, since it uses as much as digits as its factorization.

13365581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10800, while the sum is 32.

The square root of 13365581 is about 3655.8967436185. The cubic root of 13365581 is about 237.3172355698.

The spelling of 13365581 in words is "thirteen million, three hundred sixty-five thousand, five hundred eighty-one".