66336643 has 2 divisors, whose sum is σ = 66336644. Its totient is φ = 66336642.

The previous prime is 66336631. The next prime is 66336661. The reversal of 66336643 is 34663366.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66336643 - 2⁹ = 66336131 is a prime.

It is not a weakly prime, because it can be changed into another prime (66336043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33168321 + 33168322.

It is an arithmetic number, because the mean of its divisors is an integer number (33168322).

Almost surely, 2^66336643 is an apocalyptic number.

66336643 is a deficient number, since it is larger than the sum of its proper divisors (1).

66336643 is an equidigital number, since it uses as much as digits as its factorization.

66336643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 139968, while the sum is 37.

The square root of 66336643 is about 8144.7309961717. The cubic root of 66336643 is about 404.8099357124.

The spelling of 66336643 in words is "sixty-six million, three hundred thirty-six thousand, six hundred forty-three".