91999999999900 has 36 divisors (see below), whose sum is σ = 206524137937320. Its totient is φ = 35531034481600.

The previous prime is 91999999999883. The next prime is 91999999999903. The reversal of 91999999999900 is 999999999919.

It is a super-9 number, since 9×91999999999900⁹ (a number of 127 digits) contains 999999999 as substring.

It is a Harshad number since it is a multiple of its sum of digits (100).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91999999999903) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15862066066 + ... + 15862071865.

It is an arithmetic number, because the mean of its divisors is an integer number (5736781609370).

Almost surely, 2^{91999999999900} is an apocalyptic number.

It is an amenable number.

91999999999900 is an abundant number, since it is smaller than the sum of its proper divisors (114524137937420).

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

91999999999900 is a wasteful number, since it uses less digits than its factorization.

91999999999900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31724137974 (or 31724137967 counting only the distinct ones).

The product of its (nonzero) digits is 31381059609, while the sum is 100.

The spelling of 91999999999900 in words is "ninety-one trillion, nine hundred ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred".