221652166 has 4 divisors (see below), whose sum is σ = 332478252. Its totient is φ = 110826082.

The previous prime is 221652121. The next prime is 221652169. The reversal of 221652166 is 661256122.

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

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 a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221652169) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55413040 + ... + 55413043.

It is an arithmetic number, because the mean of its divisors is an integer number (83119563).

Almost surely, 2^221652166 is an apocalyptic number.

221652166 is a deficient number, since it is larger than the sum of its proper divisors (110826086).

221652166 is a wasteful number, since it uses less digits than its factorization.

221652166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110826085.

The product of its digits is 8640, while the sum is 31.

The square root of 221652166 is about 14887.9873052068. The cubic root of 221652166 is about 605.1884903207.

The spelling of 221652166 in words is "two hundred twenty-one million, six hundred fifty-two thousand, one hundred sixty-six".