91673280 has 168 divisors, whose sum is σ = 318973200. Its totient is φ = 24164352.

The previous prime is 91673279. The next prime is 91673287. The reversal of 91673280 is 8237619.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

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

It is not an unprimeable number, because it can be changed into a prime (91673287) 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, 400206 + ... + 400434.

It is an arithmetic number, because the mean of its divisors is an integer number (1898650).

Almost surely, 2^91673280 is an apocalyptic number.

91673280 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 91673280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (159486600).

91673280 is an abundant number, since it is smaller than the sum of its proper divisors (227299920).

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

91673280 is a wasteful number, since it uses less digits than its factorization.

91673280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391 (or 378 counting only the distinct ones).

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

The square root of 91673280 is about 9574.6164414038. The cubic root of 91673280 is about 450.9007144567.

The spelling of 91673280 in words is "ninety-one million, six hundred seventy-three thousand, two hundred eighty".