66216433 has 2 divisors, whose sum is σ = 66216434. Its totient is φ = 66216432.

The previous prime is 66216427. The next prime is 66216443. The reversal of 66216433 is 33461266.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 57881664 + 8334769 = 7608^2 + 2887^2 .

It is a cyclic number.

It is not a de Polignac number, because 66216433 - 2⁵ = 66216401 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66216395 and 66216404.

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

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33108216 + 33108217.

It is an arithmetic number, because the mean of its divisors is an integer number (33108217).

Almost surely, 2^66216433 is an apocalyptic number.

It is an amenable number.

66216433 is a deficient number, since it is larger than the sum of its proper divisors (1).

66216433 is an equidigital number, since it uses as much as digits as its factorization.

66216433 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 31.

The square root of 66216433 is about 8137.3480323752. The cubic root of 66216433 is about 404.5652663827.

Adding to 66216433 its reverse (33461266), we get a palindrome (99677699).

The spelling of 66216433 in words is "sixty-six million, two hundred sixteen thousand, four hundred thirty-three".