90005440 has 112 divisors (see below), whose sum is σ = 255739392. Its totient is φ = 29500416.

The previous prime is 90005437. The next prime is 90005441. The reversal of 90005440 is 4450009.

It is a tau number, because it is divible by the number of its divisors (112).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90005441) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50647 + ... + 52393.

Almost surely, 2^90005440 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 90005440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (127869696).

90005440 is an abundant number, since it is smaller than the sum of its proper divisors (165733952).

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

90005440 is a wasteful number, since it uses less digits than its factorization.

90005440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1794 (or 1784 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 90005440 is about 9487.1196893472. The cubic root of 90005440 is about 448.1495036745.

Adding to 90005440 its reverse (4450009), we get a palindrome (94455449).

The spelling of 90005440 in words is "ninety million, five thousand, four hundred forty".