221206641 has 8 divisors (see below), whose sum is σ = 295468320. Its totient is φ = 147208032.

The previous prime is 221206637. The next prime is 221206649. The reversal of 221206641 is 146602122.

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

It is not a de Polignac number, because 221206641 - 2² = 221206637 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221206649) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 63796 + ... + 67173.

It is an arithmetic number, because the mean of its divisors is an integer number (36933540).

Almost surely, 2^221206641 is an apocalyptic number.

It is an amenable number.

221206641 is a deficient number, since it is larger than the sum of its proper divisors (74261679).

221206641 is a wasteful number, since it uses less digits than its factorization.

221206641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131535.

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 221206641 is about 14873.0172123883. The cubic root of 221206641 is about 604.7827382806.

Adding to 221206641 its reverse (146602122), we get a palindrome (367808763).

The spelling of 221206641 in words is "two hundred twenty-one million, two hundred six thousand, six hundred forty-one".