1991188484 has 12 divisors (see below), whose sum is σ = 3485127744. Its totient is φ = 995437704.

The previous prime is 1991188447. The next prime is 1991188531. The reversal of 1991188484 is 4848811991.

It is a hoax number, since the sum of its digits (53) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7712 + ... + 63575.

It is an arithmetic number, because the mean of its divisors is an integer number (290427312).

Almost surely, 2^1991188484 is an apocalyptic number.

It is an amenable number.

1991188484 is a deficient number, since it is larger than the sum of its proper divisors (1493939260).

1991188484 is a wasteful number, since it uses less digits than its factorization.

1991188484 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78274 (or 78272 counting only the distinct ones).

The product of its digits is 663552, while the sum is 53.

The square root of 1991188484 is about 44622.7350573673. The cubic root of 1991188484 is about 1258.0680234810.

The spelling of 1991188484 in words is "one billion, nine hundred ninety-one million, one hundred eighty-eight thousand, four hundred eighty-four".