217116965 has 16 divisors (see below), whose sum is σ = 284431728. Its totient is φ = 158132736.

The previous prime is 217116937. The next prime is 217116983. The reversal of 217116965 is 569611712.

217116965 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 33189121 + 183927844 = 5761^2 + 13562^2 .

It is a cyclic number.

It is not a de Polignac number, because 217116965 - 2¹⁴ = 217100581 is a prime.

It is a super-2 number, since 2×217116965² = 94279552981622450, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18134 + ... + 27623.

It is an arithmetic number, because the mean of its divisors is an integer number (17776983).

Almost surely, 2^217116965 is an apocalyptic number.

It is an amenable number.

217116965 is a deficient number, since it is larger than the sum of its proper divisors (67314763).

217116965 is a wasteful number, since it uses less digits than its factorization.

217116965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45848.

The product of its digits is 22680, while the sum is 38.

The square root of 217116965 is about 14734.8893786143. The cubic root of 217116965 is about 601.0324492471.

The spelling of 217116965 in words is "two hundred seventeen million, one hundred sixteen thousand, nine hundred sixty-five".