1440243221 has 2 divisors, whose sum is σ = 1440243222. Its totient is φ = 1440243220.

The previous prime is 1440243199. The next prime is 1440243223. The reversal of 1440243221 is 1223420441.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 993132196 + 447111025 = 31514^2 + 21145^2 .

It is an emirp because it is prime and its reverse (1223420441) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1440243221 - 2⁶ = 1440243157 is a prime.

Together with 1440243223, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1440243223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 720121610 + 720121611.

It is an arithmetic number, because the mean of its divisors is an integer number (720121611).

Almost surely, 2^1440243221 is an apocalyptic number.

It is an amenable number.

1440243221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1440243221 is an equidigital number, since it uses as much as digits as its factorization.

1440243221 is an evil number, because the sum of its binary digits is even.

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

The square root of 1440243221 is about 37950.5365047716. The cubic root of 1440243221 is about 1129.3068087792.

Adding to 1440243221 its reverse (1223420441), we get a palindrome (2663663662).

The spelling of 1440243221 in words is "one billion, four hundred forty million, two hundred forty-three thousand, two hundred twenty-one".