9921216 has 28 divisors (see below), whose sum is σ = 26250392. Its totient is φ = 3307008.

The previous prime is 9921199. The next prime is 9921227. The reversal of 9921216 is 6121299.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25645 + ... + 26028.

It is an arithmetic number, because the mean of its divisors is an integer number (937514).

Almost surely, 2^9921216 is an apocalyptic number.

9921216 is a gapful number since it is divisible by the number (96) formed by its first and last digit.

It is an amenable number.

9921216 is an abundant number, since it is smaller than the sum of its proper divisors (16329176).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9921216 is a wasteful number, since it uses less digits than its factorization.

9921216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51688 (or 51678 counting only the distinct ones).

The product of its digits is 1944, while the sum is 30.

The square root of 9921216 is about 3149.7961838824. The cubic root of 9921216 is about 214.8761933678.

The spelling of 9921216 in words is "nine million, nine hundred twenty-one thousand, two hundred sixteen".