216666366 has 32 divisors (see below), whose sum is σ = 512317440. Its totient is φ = 59769696.

The previous prime is 216666277. The next prime is 216666383. The reversal of 216666366 is 663666612.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 87726 + ... + 90161.

It is an arithmetic number, because the mean of its divisors is an integer number (16009920).

Almost surely, 2^216666366 is an apocalyptic number.

216666366 is an abundant number, since it is smaller than the sum of its proper divisors (295651074).

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

216666366 is a wasteful number, since it uses less digits than its factorization.

216666366 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177928.

The product of its digits is 279936, while the sum is 42.

The square root of 216666366 is about 14719.5912307374. The cubic root of 216666366 is about 600.6163721477.

The spelling of 216666366 in words is "two hundred sixteen million, six hundred sixty-six thousand, three hundred sixty-six".