216660215 has 8 divisors (see below), whose sum is σ = 260074320. Its totient is φ = 173273472.

The previous prime is 216660203. The next prime is 216660217. The reversal of 216660215 is 512066612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 216660215 - 2¹² = 216656119 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216660217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20591 + ... + 29279.

It is an arithmetic number, because the mean of its divisors is an integer number (32509290).

Almost surely, 2^216660215 is an apocalyptic number.

216660215 is a deficient number, since it is larger than the sum of its proper divisors (43414105).

216660215 is an equidigital number, since it uses as much as digits as its factorization.

216660215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13681.

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 216660215 is about 14719.3822900283. The cubic root of 216660215 is about 600.6106884071.

The spelling of 216660215 in words is "two hundred sixteen million, six hundred sixty thousand, two hundred fifteen".