1991928732 has 48 divisors (see below), whose sum is σ = 4769614080. Its totient is φ = 646668288.

The previous prime is 1991928727. The next prime is 1991928751. The reversal of 1991928732 is 2378291991.

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 179868 + ... + 190620.

It is an arithmetic number, because the mean of its divisors is an integer number (99366960).

Almost surely, 2^1991928732 is an apocalyptic number.

1991928732 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1991928732 is an abundant number, since it is smaller than the sum of its proper divisors (2777685348).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1991928732 is a wasteful number, since it uses less digits than its factorization.

1991928732 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11162 (or 11160 counting only the distinct ones).

The product of its digits is 489888, while the sum is 51.

The square root of 1991928732 is about 44631.0288028407. The cubic root of 1991928732 is about 1258.2239047490.

The spelling of 1991928732 in words is "one billion, nine hundred ninety-one million, nine hundred twenty-eight thousand, seven hundred thirty-two".