90909128 has 12 divisors (see below), whose sum is σ = 170505195. Its totient is φ = 45441080.

The previous prime is 90909127. The next prime is 90909157. The reversal of 90909128 is 82190909.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in only one way, i.e., 45454564 + 45454564 = 6742^2 + 6742^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=6742.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 90909091 and 90909100.

It is not an unprimeable number, because it can be changed into a prime (90909121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 25283 + ... + 28653.

Almost surely, 2^90909128 is an apocalyptic number.

It is an amenable number.

90909128 is a deficient number, since it is larger than the sum of its proper divisors (79596067).

90909128 is an frugal number, since it uses more digits than its factorization.

90909128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6748 (or 3373 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 38.

The square root of 90909128 is about 9534.6278375194. The cubic root of 90909128 is about 449.6443741742.

The spelling of 90909128 in words is "ninety million, nine hundred nine thousand, one hundred twenty-eight".