217216664 has 32 divisors (see below), whose sum is σ = 489964800. Its totient is φ = 88192800.

The previous prime is 217216661. The next prime is 217216691. The reversal of 217216664 is 466612712.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217216661) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 101012 + ... + 103139.

It is an arithmetic number, because the mean of its divisors is an integer number (15311400).

Almost surely, 2^217216664 is an apocalyptic number.

It is an amenable number.

217216664 is an abundant number, since it is smaller than the sum of its proper divisors (272748136).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

217216664 is a wasteful number, since it uses less digits than its factorization.

217216664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204183 (or 204179 counting only the distinct ones).

The product of its digits is 24192, while the sum is 35.

The square root of 217216664 is about 14738.2720832532. The cubic root of 217216664 is about 601.1244321782.

The spelling of 217216664 in words is "two hundred seventeen million, two hundred sixteen thousand, six hundred sixty-four".