91723320 has 256 divisors, whose sum is σ = 338688000. Its totient is φ = 21938688.

The previous prime is 91723309. The next prime is 91723339. The reversal of 91723320 is 2332719.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 659811 + ... + 659949.

It is an arithmetic number, because the mean of its divisors is an integer number (1323000).

Almost surely, 2^91723320 is an apocalyptic number.

91723320 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 91723320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (169344000).

91723320 is an abundant number, since it is smaller than the sum of its proper divisors (246964680).

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

91723320 is a wasteful number, since it uses less digits than its factorization.

91723320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 219 (or 209 counting only the distinct ones).

The product of its (nonzero) digits is 2268, while the sum is 27.

The square root of 91723320 is about 9577.2292444109. The cubic root of 91723320 is about 450.9827411484.

The spelling of 91723320 in words is "ninety-one million, seven hundred twenty-three thousand, three hundred twenty".