91273680 has 120 divisors (see below), whose sum is σ = 324601992. Its totient is φ = 22904832.

The previous prime is 91273673. The next prime is 91273681. The reversal of 91273680 is 8637219.

It can be written as a sum of positive squares in 4 ways, for example, as 11778624 + 79495056 = 3432^2 + 8916^2 .

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91273681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8512 + ... + 15968.

Almost surely, 2^91273680 is an apocalyptic number.

91273680 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91273680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (162300996).

91273680 is an abundant number, since it is smaller than the sum of its proper divisors (233328312).

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

91273680 is a wasteful number, since it uses less digits than its factorization.

91273680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7493 (or 7484 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 91273680 is about 9553.7259747179. The cubic root of 91273680 is about 450.2446077545.

The spelling of 91273680 in words is "ninety-one million, two hundred seventy-three thousand, six hundred eighty".