9915681 has 4 divisors (see below), whose sum is σ = 13220912. Its totient is φ = 6610452.

The previous prime is 9915679. The next prime is 9915683. The reversal of 9915681 is 1865199.

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 an interprime number because it is at equal distance from previous prime (9915679) and next prime (9915683).

It is not a de Polignac number, because 9915681 - 2¹ = 9915679 is a prime.

It is a super-2 number, since 2×9915681² = 196641459387522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9915683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1652611 + ... + 1652616.

It is an arithmetic number, because the mean of its divisors is an integer number (3305228).

Almost surely, 2^9915681 is an apocalyptic number.

It is an amenable number.

9915681 is a deficient number, since it is larger than the sum of its proper divisors (3305231).

9915681 is a wasteful number, since it uses less digits than its factorization.

9915681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3305230.

The product of its digits is 19440, while the sum is 39.

The square root of 9915681 is about 3148.9174330236. The cubic root of 9915681 is about 214.8362264601.

The spelling of 9915681 in words is "nine million, nine hundred fifteen thousand, six hundred eighty-one".