221666002 has 4 divisors (see below), whose sum is σ = 332499006. Its totient is φ = 110833000.

The previous prime is 221665987. The next prime is 221666041. The reversal of 221666002 is 200666122.

221666002 is digitally balanced in base 3, 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., 221444161 + 221841 = 14881^2 + 471^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55416499 + ... + 55416502.

Almost surely, 2^221666002 is an apocalyptic number.

221666002 is a deficient number, since it is larger than the sum of its proper divisors (110833004).

221666002 is a wasteful number, since it uses less digits than its factorization.

221666002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110833003.

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 221666002 is about 14888.4519678844. The cubic root of 221666002 is about 605.2010824433.

The spelling of 221666002 in words is "two hundred twenty-one million, six hundred sixty-six thousand, two".