991309132 has 24 divisors (see below), whose sum is σ = 1893442320. Its totient is φ = 450370560.

The previous prime is 991309093. The next prime is 991309139. The reversal of 991309132 is 231903199.

991309132 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 991309091 and 991309100.

It is not an unprimeable number, because it can be changed into a prime (991309139) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 110844 + ... + 119452.

It is an arithmetic number, because the mean of its divisors is an integer number (78893430).

Almost surely, 2^991309132 is an apocalyptic number.

It is an amenable number.

991309132 is a deficient number, since it is larger than the sum of its proper divisors (902133188).

991309132 is a wasteful number, since it uses less digits than its factorization.

991309132 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11241 (or 11239 counting only the distinct ones).

The product of its (nonzero) digits is 13122, while the sum is 37.

The square root of 991309132 is about 31485.0620453573. The cubic root of 991309132 is about 997.0946108892.

The spelling of 991309132 in words is "nine hundred ninety-one million, three hundred nine thousand, one hundred thirty-two".