217080869 has 2 divisors, whose sum is σ = 217080870. Its totient is φ = 217080868.

The previous prime is 217080847. The next prime is 217080881. The reversal of 217080869 is 968080712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 202350625 + 14730244 = 14225^2 + 3838^2 .

It is a cyclic number.

It is not a de Polignac number, because 217080869 - 2¹² = 217076773 is a prime.

It is a super-2 number, since 2×217080869² = 94248207371590322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (217080839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108540434 + 108540435.

It is an arithmetic number, because the mean of its divisors is an integer number (108540435).

Almost surely, 2^217080869 is an apocalyptic number.

It is an amenable number.

217080869 is a deficient number, since it is larger than the sum of its proper divisors (1).

217080869 is an equidigital number, since it uses as much as digits as its factorization.

217080869 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48384, while the sum is 41.

The square root of 217080869 is about 14733.6644796873. The cubic root of 217080869 is about 600.9991399052. Note that the first 3 decimals are identical.

The spelling of 217080869 in words is "two hundred seventeen million, eighty thousand, eight hundred sixty-nine".