28198291 has 16 divisors (see below), whose sum is σ = 32915808. Its totient is φ = 23872000.

The previous prime is 28198273. The next prime is 28198301. The reversal of 28198291 is 19289182.

It is a cyclic number.

It is not a de Polignac number, because 28198291 - 2⁹ = 28197779 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28198211) 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 15 ways as a sum of consecutive naturals, for example, 18141 + ... + 19633.

It is an arithmetic number, because the mean of its divisors is an integer number (2057238).

Almost surely, 2^28198291 is an apocalyptic number.

28198291 is a deficient number, since it is larger than the sum of its proper divisors (4717517).

28198291 is a wasteful number, since it uses less digits than its factorization.

28198291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1622.

The product of its digits is 20736, while the sum is 40.

The square root of 28198291 is about 5310.2063048435. The cubic root of 28198291 is about 304.3740310465.

The spelling of 28198291 in words is "twenty-eight million, one hundred ninety-eight thousand, two hundred ninety-one".