91991543200 has 36 divisors (see below), whose sum is σ = 224574356790. Its totient is φ = 36796616960.

The previous prime is 91991543183. The next prime is 91991543209. The reversal of 91991543200 is 234519919.

It can be written as a sum of positive squares in 3 ways, for example, as 57176461456 + 34815081744 = 239116^2 + 186588^2 .

It is not an unprimeable number, because it can be changed into a prime (91991543209) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 57493915 + ... + 57495514.

Almost surely, 2^91991543200 is an apocalyptic number.

It is an amenable number.

91991543200 is an abundant number, since it is smaller than the sum of its proper divisors (132582813590).

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

91991543200 is a wasteful number, since it uses less digits than its factorization.

91991543200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114989449 (or 114989436 counting only the distinct ones).

The product of its (nonzero) digits is 87480, while the sum is 43.

The spelling of 91991543200 in words is "ninety-one billion, nine hundred ninety-one million, five hundred forty-three thousand, two hundred".