1289689 has 4 divisors (see below), whose sum is σ = 1294720. Its totient is φ = 1284660.

The previous prime is 1289677. The next prime is 1289711. The reversal of 1289689 is 9869821.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1289689 - 2⁵ = 1289657 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1289789) 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 in 3 ways as a sum of consecutive naturals, for example, 2109 + ... + 2650.

It is an arithmetic number, because the mean of its divisors is an integer number (323680).

2^1289689 is an apocalyptic number.

It is an amenable number.

1289689 is a deficient number, since it is larger than the sum of its proper divisors (5031).

1289689 is an equidigital number, since it uses as much as digits as its factorization.

1289689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5030.

The product of its digits is 62208, while the sum is 43.

The square root of 1289689 is about 1135.6447507914. The cubic root of 1289689 is about 108.8499745639.

The spelling of 1289689 in words is "one million, two hundred eighty-nine thousand, six hundred eighty-nine".