90720684 has 36 divisors (see below), whose sum is σ = 229844160. Its totient is φ = 30171360.

The previous prime is 90720599. The next prime is 90720689. The reversal of 90720684 is 48602709.

It is a tau number, because it is divible by the number of its divisors (36).

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 (90720689) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 14614 + ... + 19874.

It is an arithmetic number, because the mean of its divisors is an integer number (6384560).

Almost surely, 2^90720684 is an apocalyptic number.

It is an amenable number.

90720684 is an abundant number, since it is smaller than the sum of its proper divisors (139123476).

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

90720684 is a wasteful number, since it uses less digits than its factorization.

90720684 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5750 (or 5745 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 90720684 is about 9524.7406263898. The cubic root of 90720684 is about 449.3334725047. Note that the first 3 decimals are identical.

The spelling of 90720684 in words is "ninety million, seven hundred twenty thousand, six hundred eighty-four".