90040 has 16 divisors (see below), whose sum is σ = 202680. Its totient is φ = 36000.

The previous prime is 90031. The next prime is 90053. The reversal of 90040 is 4009.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 90040.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1086 + ... + 1165.

2⁹⁰⁰⁴⁰ is an apocalyptic number.

It is an amenable number.

90040 is an abundant number, since it is smaller than the sum of its proper divisors (112640).

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101340).

90040 is a wasteful number, since it uses less digits than its factorization.

90040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2262 (or 2258 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 90040 is about 300.0666592609. The cubic root of 90040 is about 44.8206856004.

Adding to 90040 its reverse (4009), we get a palindrome (94049).

The spelling of 90040 in words is "ninety thousand, forty".