28321819 has 2 divisors, whose sum is σ = 28321820. Its totient is φ = 28321818.

The previous prime is 28321801. The next prime is 28321831. The reversal of 28321819 is 91812382.

28321819 is nontrivially palindromic in base 2.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28321819 - 2⁷ = 28321691 is a prime.

It is a super-2 number, since 2×28321819² = 1604250862937522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28321619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14160909 + 14160910.

It is an arithmetic number, because the mean of its divisors is an integer number (14160910).

Almost surely, 2^28321819 is an apocalyptic number.

28321819 is a deficient number, since it is larger than the sum of its proper divisors (1).

28321819 is an equidigital number, since it uses as much as digits as its factorization.

28321819 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6912, while the sum is 34.

The square root of 28321819 is about 5321.8247810314. The cubic root of 28321819 is about 304.8178398072.

The spelling of 28321819 in words is "twenty-eight million, three hundred twenty-one thousand, eight hundred nineteen".