90099181 has 8 divisors (see below), whose sum is σ = 94792824. Its totient is φ = 85524480.

The previous prime is 90099179. The next prime is 90099187. The reversal of 90099181 is 18199009.

It can be written as a sum of positive squares in 4 ways, for example, as 2975625 + 87123556 = 1725^2 + 9334^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 90099181 - 2¹ = 90099179 is a prime.

It is a super-2 number, since 2×90099181² = 16235724833741522, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 90099181.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90099187) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28180 + ... + 31213.

It is an arithmetic number, because the mean of its divisors is an integer number (11849103).

Almost surely, 2^90099181 is an apocalyptic number.

It is an amenable number.

90099181 is a deficient number, since it is larger than the sum of its proper divisors (4693643).

90099181 is a wasteful number, since it uses less digits than its factorization.

90099181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59471.

The product of its (nonzero) digits is 5832, while the sum is 37.

The square root of 90099181 is about 9492.0588388400. The cubic root of 90099181 is about 448.3050328163.

The spelling of 90099181 in words is "ninety million, ninety-nine thousand, one hundred eighty-one".