66398219 has 2 divisors, whose sum is σ = 66398220. Its totient is φ = 66398218.

The previous prime is 66398207. The next prime is 66398261. The reversal of 66398219 is 91289366.

66398219 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66398219 - 2⁴ = 66398203 is a prime.

It is a super-2 number, since 2×66398219² = 8817446972743922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66398219.

It is not a weakly prime, because it can be changed into another prime (66398279) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33199109 + 33199110.

It is an arithmetic number, because the mean of its divisors is an integer number (33199110).

Almost surely, 2^66398219 is an apocalyptic number.

66398219 is a deficient number, since it is larger than the sum of its proper divisors (1).

66398219 is an equidigital number, since it uses as much as digits as its factorization.

66398219 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 139968, while the sum is 44.

The square root of 66398219 is about 8148.5102319381. The cubic root of 66398219 is about 404.9351499071.

The spelling of 66398219 in words is "sixty-six million, three hundred ninety-eight thousand, two hundred nineteen".