991013952 has 168 divisors, whose sum is σ = 2796637536. Its totient is φ = 309504000.

The previous prime is 991013927. The next prime is 991013977. The reversal of 991013952 is 259310199.

It is an interprime number because it is at equal distance from previous prime (991013927) and next prime (991013977).

It is a self number, because there is not a number n which added to its sum of digits gives 991013952.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7564927 + ... + 7565057.

It is an arithmetic number, because the mean of its divisors is an integer number (16646652).

Almost surely, 2^991013952 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 991013952, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1398318768).

991013952 is an abundant number, since it is smaller than the sum of its proper divisors (1805623584).

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

991013952 is a wasteful number, since it uses less digits than its factorization.

991013952 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249 (or 208 counting only the distinct ones).

The product of its (nonzero) digits is 21870, while the sum is 39.

The square root of 991013952 is about 31480.3740765576. The cubic root of 991013952 is about 996.9956334879.

The spelling of 991013952 in words is "nine hundred ninety-one million, thirteen thousand, nine hundred fifty-two".