217216671 has 16 divisors (see below), whose sum is σ = 333193728. Its totient is φ = 123300000.

The previous prime is 217216661. The next prime is 217216691. The reversal of 217216671 is 176612712.

It is not a de Polignac number, because 217216671 - 2¹⁹ = 216692383 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217216621) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31080 + ... + 37421.

It is an arithmetic number, because the mean of its divisors is an integer number (20824608).

Almost surely, 2^217216671 is an apocalyptic number.

217216671 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

217216671 is a deficient number, since it is larger than the sum of its proper divisors (115977057).

217216671 is a wasteful number, since it uses less digits than its factorization.

217216671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68662.

The product of its digits is 7056, while the sum is 33.

The square root of 217216671 is about 14738.2723207301. The cubic root of 217216671 is about 601.1244386354.

The spelling of 217216671 in words is "two hundred seventeen million, two hundred sixteen thousand, six hundred seventy-one".