9921312 has 48 divisors (see below), whose sum is σ = 28939680. Its totient is φ = 3306816.

The previous prime is 9921311. The next prime is 9921323. The reversal of 9921312 is 2131299.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nude number because it is divisible by every one of its digits.

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (9921311) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4878 + ... + 6605.

It is an arithmetic number, because the mean of its divisors is an integer number (602910).

Almost surely, 2^9921312 is an apocalyptic number.

It is an amenable number.

9921312 is an abundant number, since it is smaller than the sum of its proper divisors (19018368).

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

9921312 is a wasteful number, since it uses less digits than its factorization.

9921312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11502 (or 11488 counting only the distinct ones).

The product of its digits is 972, while the sum is 27.

The square root of 9921312 is about 3149.8114229268. The cubic root of 9921312 is about 214.8768864297.

Subtracting from 9921312 its sum of digits (27), we obtain a triangular number (9921285 = T₄₄₅₄).

It can be divided in two parts, 99213 and 12, that added together give a square (99225 = 315²).

The spelling of 9921312 in words is "nine million, nine hundred twenty-one thousand, three hundred twelve".