91097280 has 168 divisors, whose sum is σ = 320478912. Its totient is φ = 23740416.

The previous prime is 91097261. The next prime is 91097291. The reversal of 91097280 is 8279019.

It is a happy number.

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 135024 + ... + 135696.

Almost surely, 2^91097280 is an apocalyptic number.

91097280 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 91097280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (160239456).

91097280 is an abundant number, since it is smaller than the sum of its proper divisors (229381632).

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

91097280 is a wasteful number, since it uses less digits than its factorization.

91097280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 743 (or 730 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The square root of 91097280 is about 9544.4895096595. The cubic root of 91097280 is about 449.9543657428.

The spelling of 91097280 in words is "ninety-one million, ninety-seven thousand, two hundred eighty".