221902866 has 12 divisors (see below), whose sum is σ = 480789582. Its totient is φ = 73967616.

The previous prime is 221902859. The next prime is 221902871. The reversal of 221902866 is 668209122.

It is a happy number.

221902866 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 192515625 + 29387241 = 13875^2 + 5421^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 221902866.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6163951 + ... + 6163986.

Almost surely, 2^221902866 is an apocalyptic number.

221902866 is an abundant number, since it is smaller than the sum of its proper divisors (258886716).

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

221902866 is a wasteful number, since it uses less digits than its factorization.

221902866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12327945 (or 12327942 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 221902866 is about 14896.4044655078. The cubic root of 221902866 is about 605.4165707885.

The spelling of 221902866 in words is "two hundred twenty-one million, nine hundred two thousand, eight hundred sixty-six".