28189090 has 8 divisors (see below), whose sum is σ = 50740380. Its totient is φ = 11275632.

The previous prime is 28189069. The next prime is 28189151. The reversal of 28189090 is 9098182.

It can be written as a sum of positive squares in 2 ways, for example, as 25010001 + 3179089 = 5001^2 + 1783^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1409445 + ... + 1409464.

Almost surely, 2^28189090 is an apocalyptic number.

28189090 is a deficient number, since it is larger than the sum of its proper divisors (22551290).

28189090 is a wasteful number, since it uses less digits than its factorization.

28189090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2818916.

The product of its (nonzero) digits is 10368, while the sum is 37.

The square root of 28189090 is about 5309.3398836390. The cubic root of 28189090 is about 304.3409220646.

The spelling of 28189090 in words is "twenty-eight million, one hundred eighty-nine thousand, ninety".