1991091200120 has 32 divisors (see below), whose sum is σ = 4887223855920. Its totient is φ = 724033163520.

The previous prime is 1991091200089. The next prime is 1991091200297. The reversal of 1991091200120 is 210021901991.

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 7 ways as a sum of consecutive naturals, for example, 2262603197 + ... + 2262604076.

Almost surely, 2^{1991091200120} is an apocalyptic number.

1991091200120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1991091200120 is an abundant number, since it is smaller than the sum of its proper divisors (2896132655800).

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

1991091200120 is a wasteful number, since it uses less digits than its factorization.

1991091200120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4525207295 (or 4525207291 counting only the distinct ones).

The product of its (nonzero) digits is 2916, while the sum is 35.

The spelling of 1991091200120 in words is "one trillion, nine hundred ninety-one billion, ninety-one million, two hundred thousand, one hundred twenty".