13316581 has 4 divisors (see below), whose sum is σ = 13325472. Its totient is φ = 13307692.

The previous prime is 13316573. The next prime is 13316591. The reversal of 13316581 is 18561331.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 18561331 = 17 ⋅1091843.

It is a cyclic number.

It is not a de Polignac number, because 13316581 - 2³ = 13316573 is a prime.

It is a super-2 number, since 2×13316581² = 354662659059122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13316521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1585 + ... + 5398.

It is an arithmetic number, because the mean of its divisors is an integer number (3331368).

Almost surely, 2^13316581 is an apocalyptic number.

It is an amenable number.

13316581 is a deficient number, since it is larger than the sum of its proper divisors (8891).

13316581 is an equidigital number, since it uses as much as digits as its factorization.

13316581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8890.

The product of its digits is 2160, while the sum is 28.

The square root of 13316581 is about 3649.1890880030. The cubic root of 13316581 is about 237.0268682411.

The spelling of 13316581 in words is "thirteen million, three hundred sixteen thousand, five hundred eighty-one".