66808519 has 2 divisors, whose sum is σ = 66808520. Its totient is φ = 66808518.

The previous prime is 66808501. The next prime is 66808523. The reversal of 66808519 is 91580866.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66808519 is a prime.

It is a super-2 number, since 2×66808519² = 8926756421946722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66808919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33404259 + 33404260.

It is an arithmetic number, because the mean of its divisors is an integer number (33404260).

Almost surely, 2^66808519 is an apocalyptic number.

66808519 is a deficient number, since it is larger than the sum of its proper divisors (1).

66808519 is an equidigital number, since it uses as much as digits as its factorization.

66808519 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 103680, while the sum is 43.

The square root of 66808519 is about 8173.6478392453. The cubic root of 66808519 is about 405.7675208163.

The spelling of 66808519 in words is "sixty-six million, eight hundred eight thousand, five hundred nineteen".