9991512 has 80 divisors (see below), whose sum is σ = 29664360. Its totient is φ = 3131136.

The previous prime is 9991489. The next prime is 9991543. The reversal of 9991512 is 2151999.

It is a super-2 number, since 2×9991512² = 199660624092288, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

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 19 ways as a sum of consecutive naturals, for example, 10563 + ... + 11469.

Almost surely, 2^9991512 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9991512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14832180).

9991512 is an abundant number, since it is smaller than the sum of its proper divisors (19672848).

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

9991512 is a wasteful number, since it uses less digits than its factorization.

9991512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 942 (or 929 counting only the distinct ones).

The product of its digits is 7290, while the sum is 36.

The square root of 9991512 is about 3160.9353046211. The cubic root of 9991512 is about 215.3824956097.

The spelling of 9991512 in words is "nine million, nine hundred ninety-one thousand, five hundred twelve".