1811911721912 has 32 divisors (see below), whose sum is σ = 3506482396800. Its totient is φ = 877308114144.

The previous prime is 1811911721833. The next prime is 1811911721929. The reversal of 1811911721912 is 2191271191181.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28616108 + ... + 28679355.

It is an arithmetic number, because the mean of its divisors is an integer number (109577574900).

Almost surely, 2^{1811911721912} is an apocalyptic number.

It is an amenable number.

1811911721912 is a deficient number, since it is larger than the sum of its proper divisors (1694570674888).

1811911721912 is a wasteful number, since it uses less digits than its factorization.

1811911721912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57295595 (or 57295591 counting only the distinct ones).

The product of its digits is 18144, while the sum is 44.

The spelling of 1811911721912 in words is "one trillion, eight hundred eleven billion, nine hundred eleven million, seven hundred twenty-one thousand, nine hundred twelve".