991157952 has 112 divisors (see below), whose sum is σ = 2880725760. Its totient is φ = 299363328.

The previous prime is 991157939. The next prime is 991157963. The reversal of 991157952 is 259751199.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 77998 + ... + 89810.

Almost surely, 2^991157952 is an apocalyptic number.

991157952 is a gapful number since it is divisible by the number (92) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 991157952, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1440362880).

991157952 is an abundant number, since it is smaller than the sum of its proper divisors (1889567808).

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

991157952 is a wasteful number, since it uses less digits than its factorization.

991157952 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11870 (or 11860 counting only the distinct ones).

The product of its digits is 255150, while the sum is 48.

The square root of 991157952 is about 31482.6611327569. The cubic root of 991157952 is about 997.0439208733.

The spelling of 991157952 in words is "nine hundred ninety-one million, one hundred fifty-seven thousand, nine hundred fifty-two".