90018728 has 8 divisors (see below), whose sum is σ = 168785130. Its totient is φ = 45009360.

The previous prime is 90018703. The next prime is 90018767. The reversal of 90018728 is 82781009.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 46485124 + 43533604 = 6818^2 + 6598^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5626163 + ... + 5626178.

Almost surely, 2^90018728 is an apocalyptic number.

It is an amenable number.

90018728 is a deficient number, since it is larger than the sum of its proper divisors (78766402).

90018728 is a wasteful number, since it uses less digits than its factorization.

90018728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11252347 (or 11252343 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 35.

The square root of 90018728 is about 9487.8199814288. The cubic root of 90018728 is about 448.1715568510.

The spelling of 90018728 in words is "ninety million, eighteen thousand, seven hundred twenty-eight".