1440209 has 2 divisors, whose sum is σ = 1440210. Its totient is φ = 1440208.

The previous prime is 1440203. The next prime is 1440211. The reversal of 1440209 is 9020441.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1113025 + 327184 = 1055^2 + 572^2 .

It is a cyclic number.

It is not a de Polignac number, because 1440209 - 2¹⁶ = 1374673 is a prime.

Together with 1440211, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1440203) 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 as a sum of consecutive naturals, namely, 720104 + 720105.

It is an arithmetic number, because the mean of its divisors is an integer number (720105).

2^1440209 is an apocalyptic number.

It is an amenable number.

1440209 is a deficient number, since it is larger than the sum of its proper divisors (1).

1440209 is an equidigital number, since it uses as much as digits as its factorization.

1440209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 1440209 is about 1200.0870801738. The cubic root of 1440209 is about 112.9297864384.

The spelling of 1440209 in words is "one million, four hundred forty thousand, two hundred nine".