90490090 has 16 divisors (see below), whose sum is σ = 163922472. Its totient is φ = 35964864.

The previous prime is 90490079. The next prime is 90490091. The reversal of 90490090 is 9009409.

It can be written as a sum of positive squares in 4 ways, for example, as 68013009 + 22477081 = 8247^2 + 4741^2 .

It is not an unprimeable number, because it can be changed into a prime (90490091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27249 + ... + 30388.

Almost surely, 2^90490090 is an apocalyptic number.

90490090 is a deficient number, since it is larger than the sum of its proper divisors (73432382).

90490090 is a wasteful number, since it uses less digits than its factorization.

90490090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57801.

The product of its (nonzero) digits is 2916, while the sum is 31.

The square root of 90490090 is about 9512.6279229243. The cubic root of 90490090 is about 448.9524439425.

Adding to 90490090 its reverse (9009409), we get a palindrome (99499499).

The spelling of 90490090 in words is "ninety million, four hundred ninety thousand, ninety".