216920666 has 8 divisors (see below), whose sum is σ = 329301504. Its totient is φ = 107153500.

The previous prime is 216920657. The next prime is 216920707. The reversal of 216920666 is 666029612.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 653210 + ... + 653541.

It is an arithmetic number, because the mean of its divisors is an integer number (41162688).

Almost surely, 2^216920666 is an apocalyptic number.

216920666 is a deficient number, since it is larger than the sum of its proper divisors (112380838).

216920666 is a wasteful number, since it uses less digits than its factorization.

216920666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1306836.

The product of its (nonzero) digits is 46656, while the sum is 38.

The square root of 216920666 is about 14728.2268450754. The cubic root of 216920666 is about 600.8512602075.

The spelling of 216920666 in words is "two hundred sixteen million, nine hundred twenty thousand, six hundred sixty-six".