221224836 has 24 divisors (see below), whose sum is σ = 589933120. Its totient is φ = 63207072.

The previous prime is 221224799. The next prime is 221224841. The reversal of 221224836 is 638422122.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1316731 + ... + 1316898.

Almost surely, 2^221224836 is an apocalyptic number.

It is an amenable number.

221224836 is an abundant number, since it is smaller than the sum of its proper divisors (368708284).

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

221224836 is a wasteful number, since it uses less digits than its factorization.

221224836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2633643 (or 2633641 counting only the distinct ones).

The product of its digits is 9216, while the sum is 30.

The square root of 221224836 is about 14873.6288779840. The cubic root of 221224836 is about 604.7993196396.

Adding to 221224836 its reverse (638422122), we get a palindrome (859646958).

The spelling of 221224836 in words is "two hundred twenty-one million, two hundred twenty-four thousand, eight hundred thirty-six".