1388789 has 2 divisors, whose sum is σ = 1388790. Its totient is φ = 1388788.

The previous prime is 1388773. The next prime is 1388791. The reversal of 1388789 is 9878831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 966289 + 422500 = 983^2 + 650^2 .

It is a cyclic number.

It is not a de Polignac number, because 1388789 - 2⁴ = 1388773 is a prime.

Together with 1388791, 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 (1388719) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 694394 + 694395.

It is an arithmetic number, because the mean of its divisors is an integer number (694395).

2^1388789 is an apocalyptic number.

It is an amenable number.

1388789 is a deficient number, since it is larger than the sum of its proper divisors (1).

1388789 is an equidigital number, since it uses as much as digits as its factorization.

1388789 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 96768, while the sum is 44.

The square root of 1388789 is about 1178.4689219492. The cubic root of 1388789 is about 111.5694835264.

The spelling of 1388789 in words is "one million, three hundred eighty-eight thousand, seven hundred eighty-nine".