217216247 has 2 divisors, whose sum is σ = 217216248. Its totient is φ = 217216246.

The previous prime is 217216201. The next prime is 217216333. The reversal of 217216247 is 742612712.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 217216247 - 2²⁰ = 216167671 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (217216147) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108608123 + 108608124.

It is an arithmetic number, because the mean of its divisors is an integer number (108608124).

Almost surely, 2^217216247 is an apocalyptic number.

217216247 is a deficient number, since it is larger than the sum of its proper divisors (1).

217216247 is an equidigital number, since it uses as much as digits as its factorization.

217216247 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9408, while the sum is 32.

The square root of 217216247 is about 14738.2579364048. The cubic root of 217216247 is about 601.1240475099.

Adding to 217216247 its reverse (742612712), we get a palindrome (959828959).

The spelling of 217216247 in words is "two hundred seventeen million, two hundred sixteen thousand, two hundred forty-seven".