90100000 has 144 divisors (see below), whose sum is σ = 239187816. Its totient is φ = 33280000.

The previous prime is 90099991. The next prime is 90100009. The reversal of 90100000 is 109.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (90099991) and next prime (90100009).

It can be written as a sum of positive squares in 12 ways, for example, as 19607184 + 70492816 = 4428^2 + 8396^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a self number, because there is not a number n which added to its sum of digits gives 90100000.

It is not an unprimeable number, because it can be changed into a prime (90100009) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1699974 + ... + 1700026.

Almost surely, 2^90100000 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 90100000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (119593908).

90100000 is an abundant number, since it is smaller than the sum of its proper divisors (149087816).

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

90100000 is an equidigital number, since it uses as much as digits as its factorization.

90100000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105 (or 77 counting only the distinct ones).

The product of its (nonzero) digits is 9, while the sum is 10.

The square root of 90100000 is about 9492.1019800674. The cubic root of 90100000 is about 448.3063911739.

Adding to 90100000 its reverse (109), we get a palindrome (90100109).

The spelling of 90100000 in words is "ninety million, one hundred thousand".