221661633 has 8 divisors (see below), whose sum is σ = 296322048. Its totient is φ = 147387824.

The previous prime is 221661631. The next prime is 221661647. The reversal of 221661633 is 336166122.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 221661633 - 2¹ = 221661631 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 221661633.

It is not an unprimeable number, because it can be changed into a prime (221661631) 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 in 7 ways as a sum of consecutive naturals, for example, 95310 + ... + 97607.

It is an arithmetic number, because the mean of its divisors is an integer number (37040256).

Almost surely, 2^221661633 is an apocalyptic number.

It is an amenable number.

221661633 is a deficient number, since it is larger than the sum of its proper divisors (74660415).

221661633 is a wasteful number, since it uses less digits than its factorization.

221661633 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 193303.

The product of its digits is 7776, while the sum is 30.

The square root of 221661633 is about 14888.3052427064. The cubic root of 221661633 is about 605.1971062796.

The spelling of 221661633 in words is "two hundred twenty-one million, six hundred sixty-one thousand, six hundred thirty-three".