991912 has 8 divisors (see below), whose sum is σ = 1859850. Its totient is φ = 495952.

The previous prime is 991909. The next prime is 991927. The reversal of 991912 is 219199.

It can be written as a sum of positive squares in only one way, i.e., 910116 + 81796 = 954^2 + 286^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61987 + ... + 62002.

2⁹⁹¹⁹¹² is an apocalyptic number.

It is an amenable number.

991912 is a deficient number, since it is larger than the sum of its proper divisors (867938).

991912 is a wasteful number, since it uses less digits than its factorization.

991912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123995 (or 123991 counting only the distinct ones).

The product of its digits is 1458, while the sum is 31.

The square root of 991912 is about 995.9477897962. The cubic root of 991912 is about 99.7296698747.

The spelling of 991912 in words is "nine hundred ninety-one thousand, nine hundred twelve".