216941866 has 16 divisors (see below), whose sum is σ = 337033800. Its totient is φ = 104606208.

The previous prime is 216941863. The next prime is 216941869. The reversal of 216941866 is 668149612.

216941866 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (216941863) and next prime (216941869).

It can be written as a sum of positive squares in 4 ways, for example, as 188265841 + 28676025 = 13721^2 + 5355^2 .

It is not an unprimeable number, because it can be changed into a prime (216941863) 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, 63826 + ... + 67138.

Almost surely, 2^216941866 is an apocalyptic number.

216941866 is a deficient number, since it is larger than the sum of its proper divisors (120091934).

216941866 is a wasteful number, since it uses less digits than its factorization.

216941866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4473.

The product of its digits is 124416, while the sum is 43.

The square root of 216941866 is about 14728.9465339514. The cubic root of 216941866 is about 600.8708336180.

The spelling of 216941866 in words is "two hundred sixteen million, nine hundred forty-one thousand, eight hundred sixty-six".