1245689 has 2 divisors, whose sum is σ = 1245690.
Its totient is φ = 1245688.
The previous prime is 1245683. The next prime is 1245691. The reversal of 1245689 is 9865421.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 1092025 + 153664 = 1045^2 + 392^2
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-1245689 is a prime.
Together with 1245691, it forms a pair of twin primes.
It is a Chen prime.
It is a plaindrome in base 10.
It is not a weakly prime, because it can be changed into another prime (1245683) by changing a digit.
It is an upside-down number.
It is a good prime.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 622844 + 622845.
It is an arithmetic number, because the mean of its divisors is an integer number (622845).
21245689 is an apocalyptic number.
It is an amenable number.
1245689 is a deficient number, since it is larger than the sum of its proper divisors (1).
1245689 is an equidigital number, since it uses as much as digits as its factorization.
1245689 is an evil number, because the sum of its binary digits is even.
The product of its digits is 17280, while the sum is 35.
The square root of 1245689 is about 1116.1043857991.
The cubic root of 1245689 is about 107.5977549593.
The spelling of 1245689 in words is "one million, two hundred forty-five thousand, six hundred eighty-nine".