1439989 has 2 divisors, whose sum is σ = 1439990. Its totient is φ = 1439988.

The previous prime is 1439969. The next prime is 1440011. The reversal of 1439989 is 9899341.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 731025 + 708964 = 855^2 + 842^2 .

It is an emirp because it is prime and its reverse (9899341) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1439989 - 2¹⁷ = 1308917 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1439909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 719994 + 719995.

It is an arithmetic number, because the mean of its divisors is an integer number (719995).

2^1439989 is an apocalyptic number.

It is an amenable number.

1439989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1439989 is an equidigital number, since it uses as much as digits as its factorization.

1439989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 69984, while the sum is 43.

The square root of 1439989 is about 1199.9954166579. The cubic root of 1439989 is about 112.9240359262.

The spelling of 1439989 in words is "one million, four hundred thirty-nine thousand, nine hundred eighty-nine".