66216443 has 2 divisors, whose sum is σ = 66216444. Its totient is φ = 66216442.

The previous prime is 66216433. The next prime is 66216461. The reversal of 66216443 is 34461266.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66216443 - 2⁴ = 66216427 is a prime.

It is not a weakly prime, because it can be changed into another prime (66216413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33108221 + 33108222.

It is an arithmetic number, because the mean of its divisors is an integer number (33108222).

Almost surely, 2^66216443 is an apocalyptic number.

66216443 is a deficient number, since it is larger than the sum of its proper divisors (1).

66216443 is an equidigital number, since it uses as much as digits as its factorization.

66216443 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20736, while the sum is 32.

The square root of 66216443 is about 8137.3486468259. The cubic root of 66216443 is about 404.5652867485.

The spelling of 66216443 in words is "sixty-six million, two hundred sixteen thousand, four hundred forty-three".