90128643 has 16 divisors (see below), whose sum is σ = 131362176. Its totient is φ = 54512640.

The previous prime is 90128641. The next prime is 90128669. The reversal of 90128643 is 34682109.

It is not a de Polignac number, because 90128643 - 2¹ = 90128641 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (90128641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15555 + ... + 20547.

It is an arithmetic number, because the mean of its divisors is an integer number (8210136).

Almost surely, 2^90128643 is an apocalyptic number.

90128643 is a deficient number, since it is larger than the sum of its proper divisors (41233533).

90128643 is a wasteful number, since it uses less digits than its factorization.

90128643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5554.

The product of its (nonzero) digits is 10368, while the sum is 33.

The square root of 90128643 is about 9493.6106408468. The cubic root of 90128643 is about 448.3538920229.

The spelling of 90128643 in words is "ninety million, one hundred twenty-eight thousand, six hundred forty-three".