91999012 has 12 divisors (see below), whose sum is σ = 183998080. Its totient is φ = 39428136.

The previous prime is 91999009. The next prime is 91999013. The reversal of 91999012 is 21099919.

91999012 is an admirable number.

It is a super-2 number, since 2×91999012² = 16927636417952288, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (91999013) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1642812 + ... + 1642867.

Almost surely, 2^91999012 is an apocalyptic number.

It is an amenable number.

91999012 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

91999012 is a wasteful number, since it uses less digits than its factorization.

91999012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3285690 (or 3285688 counting only the distinct ones).

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

The square root of 91999012 is about 9591.6115434269. The cubic root of 91999012 is about 451.4341275325.

The spelling of 91999012 in words is "ninety-one million, nine hundred ninety-nine thousand, twelve".