99991012 has 18 divisors (see below), whose sum is σ = 192339014. Its totient is φ = 45450240.

The previous prime is 99991009. The next prime is 99991033. The reversal of 99991012 is 21019999.

It can be written as a sum of positive squares in only one way, i.e., 88661056 + 11329956 = 9416^2 + 3366^2 .

It is a pancake number, because a pancake can be divided into 99991012 parts by 14141 straight cuts.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 102813 + ... + 103780.

Almost surely, 2^99991012 is an apocalyptic number.

It is an amenable number.

99991012 is a deficient number, since it is larger than the sum of its proper divisors (92348002).

99991012 is a wasteful number, since it uses less digits than its factorization.

99991012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 206619 (or 206606 counting only the distinct ones).

The product of its (nonzero) digits is 13122, while the sum is 40.

The square root of 99991012 is about 9999.5505899015. The cubic root of 99991012 is about 464.1449767445.

It can be divided in two parts, 9999 and 1012, that added together give a palindrome (11011).

The spelling of 99991012 in words is "ninety-nine million, nine hundred ninety-one thousand, twelve".