1991137132 has 24 divisors (see below), whose sum is σ = 3529354752. Its totient is φ = 982770000.

The previous prime is 1991137111. The next prime is 1991137151. The reversal of 1991137132 is 2317311991.

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 1991137091 and 1991137100.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 779257 + ... + 781807.

It is an arithmetic number, because the mean of its divisors is an integer number (147056448).

Almost surely, 2^1991137132 is an apocalyptic number.

It is an amenable number.

1991137132 is a deficient number, since it is larger than the sum of its proper divisors (1538217620).

1991137132 is a wasteful number, since it uses less digits than its factorization.

1991137132 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4989 (or 4987 counting only the distinct ones).

The product of its digits is 10206, while the sum is 37.

The square root of 1991137132 is about 44622.1596519039. The cubic root of 1991137132 is about 1258.0572083548.

The spelling of 1991137132 in words is "one billion, nine hundred ninety-one million, one hundred thirty-seven thousand, one hundred thirty-two".