66821327 has 2 divisors, whose sum is σ = 66821328. Its totient is φ = 66821326.

The previous prime is 66821323. The next prime is 66821329. The reversal of 66821327 is 72312866.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66821327 - 2² = 66821323 is a prime.

Together with 66821329, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66821323) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33410663 + 33410664.

It is an arithmetic number, because the mean of its divisors is an integer number (33410664).

Almost surely, 2^66821327 is an apocalyptic number.

66821327 is a deficient number, since it is larger than the sum of its proper divisors (1).

66821327 is an equidigital number, since it uses as much as digits as its factorization.

66821327 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24192, while the sum is 35.

The square root of 66821327 is about 8174.4312952034. The cubic root of 66821327 is about 405.7934493377.

The spelling of 66821327 in words is "sixty-six million, eight hundred twenty-one thousand, three hundred twenty-seven".