144243221 has 4 divisors (see below), whose sum is σ = 144395532. Its totient is φ = 144090912.

The previous prime is 144243179. The next prime is 144243241. The reversal of 144243221 is 122342441.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 122342441 = 13 ⋅9410957.

It can be written as a sum of positive squares in 2 ways, for example, as 116942596 + 27300625 = 10814^2 + 5225^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-144243221 is a prime.

It is a super-2 number, since 2×144243221² = 41612213608909682, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (144243241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 74726 + ... + 76631.

It is an arithmetic number, because the mean of its divisors is an integer number (36098883).

Almost surely, 2^144243221 is an apocalyptic number.

It is an amenable number.

144243221 is a deficient number, since it is larger than the sum of its proper divisors (152311).

144243221 is an equidigital number, since it uses as much as digits as its factorization.

144243221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152310.

The product of its digits is 1536, while the sum is 23.

The square root of 144243221 is about 12010.1299326860. The cubic root of 144243221 is about 524.4432143994.

Adding to 144243221 its reverse (122342441), we get a palindrome (266585662).

The spelling of 144243221 in words is "one hundred forty-four million, two hundred forty-three thousand, two hundred twenty-one".