1687289 has 2 divisors, whose sum is σ = 1687290. Its totient is φ = 1687288.

The previous prime is 1687247. The next prime is 1687297. The reversal of 1687289 is 9827861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 846400 + 840889 = 920^2 + 917^2 .

It is a cyclic number.

It is not a de Polignac number, because 1687289 - 2⁸ = 1687033 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1687489) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 843644 + 843645.

It is an arithmetic number, because the mean of its divisors is an integer number (843645).

2^1687289 is an apocalyptic number.

It is an amenable number.

1687289 is a deficient number, since it is larger than the sum of its proper divisors (1).

1687289 is an equidigital number, since it uses as much as digits as its factorization.

1687289 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48384, while the sum is 41.

The square root of 1687289 is about 1298.9568891999. The cubic root of 1687289 is about 119.0501165927.

It can be divided in two parts, 16872 and 89, that added together give a palindrome (16961).

The spelling of 1687289 in words is "one million, six hundred eighty-seven thousand, two hundred eighty-nine".