991755832812 has 24 divisors (see below), whose sum is σ = 2357759151216. Its totient is φ = 324347819328.

The previous prime is 991755832751. The next prime is 991755832819. The reversal of 991755832812 is 218238557199.

991755832812 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (991755832819) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 779681623 + ... + 779682894.

It is an arithmetic number, because the mean of its divisors is an integer number (98239964634).

Almost surely, 2^991755832812 is an apocalyptic number.

It is an amenable number.

991755832812 is an abundant number, since it is smaller than the sum of its proper divisors (1366003318404).

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

991755832812 is a wasteful number, since it uses less digits than its factorization.

991755832812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1559364577 (or 1559364575 counting only the distinct ones).

The product of its digits is 10886400, while the sum is 60.

The spelling of 991755832812 in words is "nine hundred ninety-one billion, seven hundred fifty-five million, eight hundred thirty-two thousand, eight hundred twelve".