1388669 has 2 divisors, whose sum is σ = 1388670.
Its totient is φ = 1388668.
The previous prime is 1388659. The next prime is 1388687. The reversal of 1388669 is 9668831.
It is a happy number.
It is a weak prime.
It can be written as a sum of positive squares in only one way, i.e., 1352569 + 36100 = 1163^2 + 190^2
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-1388669 is a prime.
It is a super-2 number, since 2×13886692 = 3856803183122, which contains 22 as substring.
It is a Sophie Germain prime.
It is a Curzon number.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (1388659) 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, 694334 + 694335.
It is an arithmetic number, because the mean of its divisors is an integer number (694335).
21388669 is an apocalyptic number.
It is an amenable number.
1388669 is a deficient number, since it is larger than the sum of its proper divisors (1).
1388669 is an equidigital number, since it uses as much as digits as its factorization.
1388669 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 62208, while the sum is 41.
The square root of 1388669 is about 1178.4180073302.
The cubic root of 1388669 is about 111.5662700016.
The spelling of 1388669 in words is "one million, three hundred eighty-eight thousand, six hundred sixty-nine".