221213144 has 16 divisors (see below), whose sum is σ = 416949120. Its totient is φ = 110026720.

The previous prime is 221213123. The next prime is 221213147. The reversal of 221213144 is 441312122.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221213147) 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, 70859 + ... + 73914.

It is an arithmetic number, because the mean of its divisors is an integer number (26059320).

Almost surely, 2^221213144 is an apocalyptic number.

It is an amenable number.

221213144 is a deficient number, since it is larger than the sum of its proper divisors (195735976).

221213144 is a wasteful number, since it uses less digits than its factorization.

221213144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 144970 (or 144966 counting only the distinct ones).

The product of its digits is 384, while the sum is 20.

The square root of 221213144 is about 14873.2358281579. The cubic root of 221213144 is about 604.7886646602.

Adding to 221213144 its reverse (441312122), we get a palindrome (662525266).

The spelling of 221213144 in words is "two hundred twenty-one million, two hundred thirteen thousand, one hundred forty-four".