13613381 has 4 divisors (see below), whose sum is σ = 13650252. Its totient is φ = 13576512.

The previous prime is 13613357. The next prime is 13613393. The reversal of 13613381 is 18331631.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 11628100 + 1985281 = 3410^2 + 1409^2 .

It is a cyclic number.

It is not a de Polignac number, because 13613381 - 2⁶ = 13613317 is a prime.

It is a super-2 number, since 2×13613381² = 370648284502322, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 13613381.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13613321) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17876 + ... + 18621.

It is an arithmetic number, because the mean of its divisors is an integer number (3412563).

Almost surely, 2^13613381 is an apocalyptic number.

It is an amenable number.

13613381 is a deficient number, since it is larger than the sum of its proper divisors (36871).

13613381 is an equidigital number, since it uses as much as digits as its factorization.

13613381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36870.

The product of its digits is 1296, while the sum is 26.

The square root of 13613381 is about 3689.6315534210. The cubic root of 13613381 is about 238.7748970317.

The spelling of 13613381 in words is "thirteen million, six hundred thirteen thousand, three hundred eighty-one".