9915621 has 8 divisors (see below), whose sum is σ = 13342560. Its totient is φ = 6549552.

The previous prime is 9915617. The next prime is 9915623. The reversal of 9915621 is 1265199.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 9915621 - 2² = 9915617 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9915623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14835 + ... + 15488.

It is an arithmetic number, because the mean of its divisors is an integer number (1667820).

Almost surely, 2^9915621 is an apocalyptic number.

It is an amenable number.

9915621 is a deficient number, since it is larger than the sum of its proper divisors (3426939).

9915621 is a wasteful number, since it uses less digits than its factorization.

9915621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30435.

The product of its digits is 4860, while the sum is 33.

The square root of 9915621 is about 3148.9079059255. The cubic root of 9915621 is about 214.8357931330.

The spelling of 9915621 in words is "nine million, nine hundred fifteen thousand, six hundred twenty-one".