90810090 has 192 divisors, whose sum is σ = 292481280. Its totient is φ = 19077120.

The previous prime is 90810079. The next prime is 90810143. The reversal of 90810090 is 9001809.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 653241 + ... + 653379.

It is an arithmetic number, because the mean of its divisors is an integer number (1523340).

Almost surely, 2^90810090 is an apocalyptic number.

90810090 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 90810090, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (146240640).

90810090 is an abundant number, since it is smaller than the sum of its proper divisors (201671190).

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

90810090 is a wasteful number, since it uses less digits than its factorization.

90810090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 237 (or 234 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 27.

The square root of 90810090 is about 9529.4328267741. The cubic root of 90810090 is about 449.4810313520.

Adding to 90810090 its reverse (9001809), we get a palindrome (99811899).

The spelling of 90810090 in words is "ninety million, eight hundred ten thousand, ninety".