28993219 has 4 divisors (see below), whose sum is σ = 29610144. Its totient is φ = 28376296.

The previous prime is 28993213. The next prime is 28993241. The reversal of 28993219 is 91239982.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28993219 - 2¹³ = 28985027 is a prime.

It is a super-2 number, since 2×28993219² = 1681213495963922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28993213) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 308392 + ... + 308485.

It is an arithmetic number, because the mean of its divisors is an integer number (7402536).

Almost surely, 2^28993219 is an apocalyptic number.

28993219 is a deficient number, since it is larger than the sum of its proper divisors (616925).

28993219 is an equidigital number, since it uses as much as digits as its factorization.

28993219 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 616924.

The product of its digits is 69984, while the sum is 43.

The square root of 28993219 is about 5384.5351702816. The cubic root of 28993219 is about 307.2077342877.

The spelling of 28993219 in words is "twenty-eight million, nine hundred ninety-three thousand, two hundred nineteen".