66019493 has 2 divisors, whose sum is σ = 66019494. Its totient is φ = 66019492.

The previous prime is 66019477. The next prime is 66019501. The reversal of 66019493 is 39491066.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 35736484 + 30283009 = 5978^2 + 5503^2 .

It is a cyclic number.

It is not a de Polignac number, because 66019493 - 2⁴ = 66019477 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66019403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33009746 + 33009747.

It is an arithmetic number, because the mean of its divisors is an integer number (33009747).

Almost surely, 2^66019493 is an apocalyptic number.

It is an amenable number.

66019493 is a deficient number, since it is larger than the sum of its proper divisors (1).

66019493 is an equidigital number, since it uses as much as digits as its factorization.

66019493 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 34992, while the sum is 38.

The square root of 66019493 is about 8125.2380272826. The cubic root of 66019493 is about 404.1637839499.

The spelling of 66019493 in words is "sixty-six million, nineteen thousand, four hundred ninety-three".