39666217 has 2 divisors, whose sum is σ = 39666218. Its totient is φ = 39666216.

The previous prime is 39666203. The next prime is 39666233. The reversal of 39666217 is 71266693.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 31764496 + 7901721 = 5636^2 + 2811^2 .

It is a cyclic number.

It is not a de Polignac number, because 39666217 - 2⁷ = 39666089 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 39666217.

It is not a weakly prime, because it can be changed into another prime (39666017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19833108 + 19833109.

It is an arithmetic number, because the mean of its divisors is an integer number (19833109).

Almost surely, 2^39666217 is an apocalyptic number.

It is an amenable number.

39666217 is a deficient number, since it is larger than the sum of its proper divisors (1).

39666217 is an equidigital number, since it uses as much as digits as its factorization.

39666217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 81648, while the sum is 40.

The square root of 39666217 is about 6298.1121774703. The cubic root of 39666217 is about 341.0412628551.

The spelling of 39666217 in words is "thirty-nine million, six hundred sixty-six thousand, two hundred seventeen".