217116668 has 6 divisors (see below), whose sum is σ = 379954176. Its totient is φ = 108558332.

The previous prime is 217116661. The next prime is 217116719. The reversal of 217116668 is 866611712.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217116661) 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, 27139580 + ... + 27139587.

It is an arithmetic number, because the mean of its divisors is an integer number (63325696).

Almost surely, 2^217116668 is an apocalyptic number.

It is an amenable number.

217116668 is a deficient number, since it is larger than the sum of its proper divisors (162837508).

217116668 is a wasteful number, since it uses less digits than its factorization.

217116668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54279171 (or 54279169 counting only the distinct ones).

The product of its digits is 24192, while the sum is 38.

The square root of 217116668 is about 14734.8793004897. The cubic root of 217116668 is about 601.0321751909.

The spelling of 217116668 in words is "two hundred seventeen million, one hundred sixteen thousand, six hundred sixty-eight".