1397999 has 2 divisors, whose sum is σ = 1398000.
Its totient is φ = 1397998.
The previous prime is 1397989. The next prime is 1398011. The reversal of 1397999 is 9997931.
It is a happy number.
It is a weak prime.
It is a cyclic number.
It is not a de Polignac number, because 1397999 - 24 = 1397983 is a prime.
It is a Sophie Germain prime.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (1397909) 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, 698999 + 699000.
It is an arithmetic number, because the mean of its divisors is an integer number (699000).
21397999 is an apocalyptic number.
1397999 is a deficient number, since it is larger than the sum of its proper divisors (1).
1397999 is an equidigital number, since it uses as much as digits as its factorization.
1397999 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 137781, while the sum is 47.
The square root of 1397999 is about 1182.3700774292.
The cubic root of 1397999 is about 111.8155712580.
The spelling of 1397999 in words is "one million, three hundred ninety-seven thousand, nine hundred ninety-nine".