216660105 has 24 divisors (see below), whose sum is σ = 381705480. Its totient is φ = 113656320.

The previous prime is 216660091. The next prime is 216660181. The reversal of 216660105 is 501066612.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 22810176 + 193849929 = 4776^2 + 13923^2 .

It is not a de Polignac number, because 216660105 - 2⁹ = 216659593 is a prime.

It is a super-2 number, since 2×216660105² = 93883202197222050, which contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 36720 + ... + 42209.

It is an arithmetic number, because the mean of its divisors is an integer number (15904395).

Almost surely, 2^216660105 is an apocalyptic number.

It is an amenable number.

216660105 is a deficient number, since it is larger than the sum of its proper divisors (165045375).

216660105 is a wasteful number, since it uses less digits than its factorization.

216660105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79001 (or 78998 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 216660105 is about 14719.3785534580. The cubic root of 216660105 is about 600.6105867622.

The spelling of 216660105 in words is "two hundred sixteen million, six hundred sixty thousand, one hundred five".