9991000344 has 64 divisors (see below), whose sum is σ = 26941350240. Its totient is φ = 3069296640.

The previous prime is 9991000343. The next prime is 9991000367. The reversal of 9991000344 is 4430001999.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9991000343) 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, 175014 + ... + 224970.

Almost surely, 2^9991000344 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 9991000344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13470675120).

9991000344 is an abundant number, since it is smaller than the sum of its proper divisors (16950349896).

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

9991000344 is a wasteful number, since it uses less digits than its factorization.

9991000344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50620 (or 50616 counting only the distinct ones).

The product of its (nonzero) digits is 34992, while the sum is 39.

The square root of 9991000344 is about 99954.9915912157. The cubic root of 9991000344 is about 2153.7881903478.

The spelling of 9991000344 in words is "nine billion, nine hundred ninety-one million, three hundred forty-four", and thus it is an aban number.