90090100 has 36 divisors (see below), whose sum is σ = 196730464. Its totient is φ = 35808480.

The previous prime is 90090097. The next prime is 90090101. The reversal of 90090100 is 109009.

It is a super-2 number, since 2×90090100² = 16232452236020000, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90090101) 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, 13537 + ... + 19063.

Almost surely, 2^90090100 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 90090100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98365232).

90090100 is an abundant number, since it is smaller than the sum of its proper divisors (106640364).

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

90090100 is a wasteful number, since it uses less digits than its factorization.

90090100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5704 (or 5697 counting only the distinct ones).

The product of its (nonzero) digits is 81, while the sum is 19.

The square root of 90090100 is about 9491.5804795619. The cubic root of 90090100 is about 448.2899709155.

Adding to 90090100 its reverse (109009), we get a palindrome (90199109).

The spelling of 90090100 in words is "ninety million, ninety thousand, one hundred".