212321866 has 4 divisors (see below), whose sum is σ = 318482802. Its totient is φ = 106160932.

The previous prime is 212321849. The next prime is 212321929. The reversal of 212321866 is 668123212.

212321866 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 172265625 + 40056241 = 13125^2 + 6329^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 53080465 + ... + 53080468.

Almost surely, 2^212321866 is an apocalyptic number.

212321866 is a deficient number, since it is larger than the sum of its proper divisors (106160936).

212321866 is a wasteful number, since it uses less digits than its factorization.

212321866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106160935.

The product of its digits is 6912, while the sum is 31.

The square root of 212321866 is about 14571.2685103254. The cubic root of 212321866 is about 596.5748043021.

The spelling of 212321866 in words is "two hundred twelve million, three hundred twenty-one thousand, eight hundred sixty-six".