9991323 has 16 divisors (see below), whose sum is σ = 14902560. Its totient is φ = 6615648.

The previous prime is 9991313. The next prime is 9991337. The reversal of 9991323 is 3231999.

9991323 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 9991323 - 2⁶ = 9991259 is a prime.

It is not an unprimeable number, because it can be changed into a prime (9991313) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3061 + ... + 5417.

It is an arithmetic number, because the mean of its divisors is an integer number (931410).

Almost surely, 2^9991323 is an apocalyptic number.

9991323 is a deficient number, since it is larger than the sum of its proper divisors (4911237).

9991323 is a wasteful number, since it uses less digits than its factorization.

9991323 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2523 (or 2517 counting only the distinct ones).

The product of its digits is 13122, while the sum is 36.

The square root of 9991323 is about 3160.9054082652. The cubic root of 9991323 is about 215.3811375387.

The spelling of 9991323 in words is "nine million, nine hundred ninety-one thousand, three hundred twenty-three".