1440401021 has 2 divisors, whose sum is σ = 1440401022. Its totient is φ = 1440401020.

The previous prime is 1440401003. The next prime is 1440401023. The reversal of 1440401021 is 1201040441.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1432622500 + 7778521 = 37850^2 + 2789^2 .

It is a cyclic number.

It is not a de Polignac number, because 1440401021 - 2¹⁰ = 1440399997 is a prime.

Together with 1440401023, 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 (1440401023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 720200510 + 720200511.

It is an arithmetic number, because the mean of its divisors is an integer number (720200511).

Almost surely, 2^1440401021 is an apocalyptic number.

It is an amenable number.

1440401021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1440401021 is an equidigital number, since it uses as much as digits as its factorization.

1440401021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 1440401021 is about 37952.6154698197. The cubic root of 1440401021 is about 1129.3480513749.

Adding to 1440401021 its reverse (1201040441), we get a palindrome (2641441462).

The spelling of 1440401021 in words is "one billion, four hundred forty million, four hundred one thousand, twenty-one".