221224557 has 16 divisors (see below), whose sum is σ = 318407040. Its totient is φ = 136204992.

The previous prime is 221224537. The next prime is 221224559. The reversal of 221224557 is 755422122.

It is not a de Polignac number, because 221224557 - 2¹¹ = 221222509 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221224559) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53278 + ... + 57279.

It is an arithmetic number, because the mean of its divisors is an integer number (19900440).

Almost surely, 2^221224557 is an apocalyptic number.

It is an amenable number.

221224557 is a deficient number, since it is larger than the sum of its proper divisors (97182483).

221224557 is a wasteful number, since it uses less digits than its factorization.

221224557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110612.

The product of its digits is 11200, while the sum is 30.

The square root of 221224557 is about 14873.6194989653. The cubic root of 221224557 is about 604.7990653899.

Adding to 221224557 its reverse (755422122), we get a palindrome (976646679).

The spelling of 221224557 in words is "two hundred twenty-one million, two hundred twenty-four thousand, five hundred fifty-seven".