15613381 has 4 divisors (see below), whose sum is σ = 17843872. Its totient is φ = 13382892.

The previous prime is 15613363. The next prime is 15613387. The reversal of 15613381 is 18331651.

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.

It is a cyclic number.

It is not a de Polignac number, because 15613381 - 2¹³ = 15605189 is a prime.

It is a super-2 number, since 2×15613381² = 487555332502322, 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 (15613387) 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, 1115235 + ... + 1115248.

It is an arithmetic number, because the mean of its divisors is an integer number (4460968).

Almost surely, 2^15613381 is an apocalyptic number.

It is an amenable number.

15613381 is a deficient number, since it is larger than the sum of its proper divisors (2230491).

15613381 is an equidigital number, since it uses as much as digits as its factorization.

15613381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2230490.

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

The square root of 15613381 is about 3951.3771017204. The cubic root of 15613381 is about 249.9380166335.

The spelling of 15613381 in words is "fifteen million, six hundred thirteen thousand, three hundred eighty-one".