221224151 has 16 divisors (see below), whose sum is σ = 238019040. Its totient is φ = 205201920.

The previous prime is 221224139. The next prime is 221224169. The reversal of 221224151 is 151422122.

It is a cyclic number.

It is not a de Polignac number, because 221224151 - 2¹⁰ = 221223127 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221224351) 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, 78275 + ... + 81051.

It is an arithmetic number, because the mean of its divisors is an integer number (14876190).

Almost surely, 2^221224151 is an apocalyptic number.

221224151 is a deficient number, since it is larger than the sum of its proper divisors (16794889).

221224151 is a wasteful number, since it uses less digits than its factorization.

221224151 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2914.

The product of its digits is 320, while the sum is 20.

The square root of 221224151 is about 14873.6058506335. The cubic root of 221224151 is about 604.7986954060.

Adding to 221224151 its reverse (151422122), we get a palindrome (372646273).

The spelling of 221224151 in words is "two hundred twenty-one million, two hundred twenty-four thousand, one hundred fifty-one".