28919819 has 2 divisors, whose sum is σ = 28919820. Its totient is φ = 28919818.

The previous prime is 28919747. The next prime is 28919831. The reversal of 28919819 is 91891982.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28919819 - 2⁸ = 28919563 is a prime.

It is a super-2 number, since 2×28919819² = 1672711861985522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28915819) by changing a digit.

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 as a sum of consecutive naturals, namely, 14459909 + 14459910.

It is an arithmetic number, because the mean of its divisors is an integer number (14459910).

Almost surely, 2^28919819 is an apocalyptic number.

28919819 is a deficient number, since it is larger than the sum of its proper divisors (1).

28919819 is an equidigital number, since it uses as much as digits as its factorization.

28919819 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 93312, while the sum is 47.

The square root of 28919819 is about 5377.7150352171. The cubic root of 28919819 is about 306.9482701339.

The spelling of 28919819 in words is "twenty-eight million, nine hundred nineteen thousand, eight hundred nineteen".