13856581 has 8 divisors (see below), whose sum is σ = 14745024. Its totient is φ = 12976320.

The previous prime is 13856539. The next prime is 13856593. The reversal of 13856581 is 18565831.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 13856581 - 2¹⁵ = 13823813 is a prime.

It is a super-2 number, since 2×13856581² = 384009674019122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 13856581.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13856881) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1656 + ... + 5518.

It is an arithmetic number, because the mean of its divisors is an integer number (1843128).

Almost surely, 2^13856581 is an apocalyptic number.

It is an amenable number.

13856581 is a deficient number, since it is larger than the sum of its proper divisors (888443).

13856581 is a wasteful number, since it uses less digits than its factorization.

13856581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4091.

The product of its digits is 28800, while the sum is 37.

The square root of 13856581 is about 3722.4428806900. The cubic root of 13856581 is about 240.1883995218.

The spelling of 13856581 in words is "thirteen million, eight hundred fifty-six thousand, five hundred eighty-one".