991001011012 has 48 divisors (see below), whose sum is σ = 1829356522560. Its totient is φ = 468438018048.

The previous prime is 991001010997. The next prime is 991001011037. The reversal of 991001011012 is 210110100199.

It is a super-2 number, since 2×991001011012² (a number of 25 digits) contains 22 as substring.

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, 97218588 + ... + 97228780.

It is an arithmetic number, because the mean of its divisors is an integer number (38111594220).

Almost surely, 2^991001011012 is an apocalyptic number.

It is an amenable number.

991001011012 is a deficient number, since it is larger than the sum of its proper divisors (838355511548).

991001011012 is a wasteful number, since it uses less digits than its factorization.

991001011012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12772 (or 12770 counting only the distinct ones).

The product of its (nonzero) digits is 162, while the sum is 25.

The spelling of 991001011012 in words is "nine hundred ninety-one billion, one million, eleven thousand, twelve".