28928819 has 4 divisors (see below), whose sum is σ = 29137080. Its totient is φ = 28720560.

The previous prime is 28928813. The next prime is 28928833. The reversal of 28928819 is 91882982.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 91882982 = 2 ⋅45941491.

It is a cyclic number.

It is not a de Polignac number, because 28928819 - 2⁴ = 28928803 is a prime.

It is a super-2 number, since 2×28928819² = 1673753137469522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28928813) 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, 103922 + ... + 104199.

It is an arithmetic number, because the mean of its divisors is an integer number (7284270).

Almost surely, 2^28928819 is an apocalyptic number.

28928819 is a deficient number, since it is larger than the sum of its proper divisors (208261).

28928819 is a wasteful number, since it uses less digits than its factorization.

28928819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 208260.

The product of its digits is 165888, while the sum is 47.

The square root of 28928819 is about 5378.5517567464. The cubic root of 28928819 is about 306.9801081376.

It can be divided in two parts, 2892 and 8819, that added together give a palindrome (11711).

The spelling of 28928819 in words is "twenty-eight million, nine hundred twenty-eight thousand, eight hundred nineteen".