909090720 has 288 divisors, whose sum is σ = 3302208000. Its totient is φ = 227100672.

The previous prime is 909090673. The next prime is 909090737. The reversal of 909090720 is 27090909.

It is a tau number, because it is divible by the number of its divisors (288).

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4076529 + ... + 4076751.

It is an arithmetic number, because the mean of its divisors is an integer number (11466000).

Almost surely, 2^909090720 is an apocalyptic number.

909090720 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 909090720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1651104000).

909090720 is an abundant number, since it is smaller than the sum of its proper divisors (2393117280).

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

909090720 is a wasteful number, since it uses less digits than its factorization.

909090720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 412 (or 401 counting only the distinct ones).

The product of its (nonzero) digits is 10206, while the sum is 36.

The square root of 909090720 is about 30151.1313220582. The cubic root of 909090720 is about 968.7292389862.

The spelling of 909090720 in words is "nine hundred nine million, ninety thousand, seven hundred twenty".