9916581 has 4 divisors (see below), whose sum is σ = 13222112. Its totient is φ = 6611052.

The previous prime is 9916573. The next prime is 9916583. The reversal of 9916581 is 1856199.

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 not a de Polignac number, because 9916581 - 2³ = 9916573 is a prime.

It is a super-2 number, since 2×9916581² = 196677157459122, 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 (9916583) 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, 1652761 + ... + 1652766.

It is an arithmetic number, because the mean of its divisors is an integer number (3305528).

Almost surely, 2^9916581 is an apocalyptic number.

It is an amenable number.

9916581 is a deficient number, since it is larger than the sum of its proper divisors (3305531).

9916581 is a wasteful number, since it uses less digits than its factorization.

9916581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3305530.

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

The square root of 9916581 is about 3149.0603360368. The cubic root of 9916581 is about 214.8427261567.

The spelling of 9916581 in words is "nine million, nine hundred sixteen thousand, five hundred eighty-one".