991332113 has 4 divisors (see below), whose sum is σ = 996809268. Its totient is φ = 985854960.

The previous prime is 991332109. The next prime is 991332127. The reversal of 991332113 is 311233199.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 135652609 + 855679504 = 11647^2 + 29252^2 .

It is a cyclic number.

It is not a de Polignac number, because 991332113 - 2² = 991332109 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 991332113.

It is not an unprimeable number, because it can be changed into a prime (991332103) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2738306 + ... + 2738667.

It is an arithmetic number, because the mean of its divisors is an integer number (249202317).

Almost surely, 2^991332113 is an apocalyptic number.

It is an amenable number.

991332113 is a deficient number, since it is larger than the sum of its proper divisors (5477155).

991332113 is a wasteful number, since it uses less digits than its factorization.

991332113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5477154.

The product of its digits is 4374, while the sum is 32.

The square root of 991332113 is about 31485.4269940873. The cubic root of 991332113 is about 997.1023158702.

The spelling of 991332113 in words is "nine hundred ninety-one million, three hundred thirty-two thousand, one hundred thirteen".