28684219 has 16 divisors (see below), whose sum is σ = 31842720. Its totient is φ = 25715200.

The previous prime is 28684211. The next prime is 28684223. The reversal of 28684219 is 91248682.

It is a cyclic number.

It is not a de Polignac number, because 28684219 - 2³ = 28684211 is a prime.

It is a super-2 number, since 2×28684219² = 1645568839279922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28684211) 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, 40569 + ... + 41269.

It is an arithmetic number, because the mean of its divisors is an integer number (1990170).

Almost surely, 2^28684219 is an apocalyptic number.

28684219 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

28684219 is a deficient number, since it is larger than the sum of its proper divisors (3158501).

28684219 is a wasteful number, since it uses less digits than its factorization.

28684219 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 830.

The product of its digits is 55296, while the sum is 40.

The square root of 28684219 is about 5355.7650247187. The cubic root of 28684219 is about 306.1124616887.

The spelling of 28684219 in words is "twenty-eight million, six hundred eighty-four thousand, two hundred nineteen".