15981113 has 4 divisors (see below), whose sum is σ = 16675968. Its totient is φ = 15286260.

The previous prime is 15981101. The next prime is 15981127. The reversal of 15981113 is 31118951.

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 an emirpimes, since its reverse is a distinct semiprime: 31118951 = 73 ⋅426287.

It is not a de Polignac number, because 15981113 - 2¹⁰ = 15980089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15981193) 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, 347393 + ... + 347438.

It is an arithmetic number, because the mean of its divisors is an integer number (4168992).

Almost surely, 2^15981113 is an apocalyptic number.

It is an amenable number.

15981113 is a deficient number, since it is larger than the sum of its proper divisors (694855).

15981113 is an equidigital number, since it uses as much as digits as its factorization.

15981113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 694854.

The product of its digits is 1080, while the sum is 29.

The square root of 15981113 is about 3997.6384278721. The cubic root of 15981113 is about 251.8850204027.

The spelling of 15981113 in words is "fifteen million, nine hundred eighty-one thousand, one hundred thirteen".