221215206 has 8 divisors (see below), whose sum is σ = 442430424. Its totient is φ = 73738400.

The previous prime is 221215201. The next prime is 221215207. The reversal of 221215206 is 602512122.

It is a happy number.

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

221215206 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221215201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18434595 + ... + 18434606.

It is an arithmetic number, because the mean of its divisors is an integer number (55303803).

Almost surely, 2^221215206 is an apocalyptic number.

221215206 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

221215206 is a wasteful number, since it uses less digits than its factorization.

221215206 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36869206.

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 221215206 is about 14873.3051471420. The cubic root of 221215206 is about 604.7905437986.

Adding to 221215206 its reverse (602512122), we get a palindrome (823727328).

The spelling of 221215206 in words is "two hundred twenty-one million, two hundred fifteen thousand, two hundred six".