28000019 has 2 divisors, whose sum is σ = 28000020. Its totient is φ = 28000018.

The previous prime is 27999943. The next prime is 28000031. The reversal of 28000019 is 91000082.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28000019 is a prime.

It is a super-2 number, since 2×28000019² = 1568002128000722, which contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (28000069) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14000009 + 14000010.

It is an arithmetic number, because the mean of its divisors is an integer number (14000010).

Almost surely, 2^28000019 is an apocalyptic number.

28000019 is a deficient number, since it is larger than the sum of its proper divisors (1).

28000019 is an equidigital number, since it uses as much as digits as its factorization.

28000019 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 28000019 is about 5291.5044174601. The cubic root of 28000019 is about 303.6589658723.

The spelling of 28000019 in words is "twenty-eight million, nineteen", and thus it is an aban number and an uban number.