1709989 has 2 divisors, whose sum is σ = 1709990. Its totient is φ = 1709988.

The previous prime is 1709971. The next prime is 1709993. The reversal of 1709989 is 9899071.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1361889 + 348100 = 1167^2 + 590^2 .

It is a cyclic number.

It is not a de Polignac number, because 1709989 - 2⁷ = 1709861 is a prime.

1709989 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1709909) 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, 854994 + 854995.

It is an arithmetic number, because the mean of its divisors is an integer number (854995).

2^1709989 is an apocalyptic number.

It is an amenable number.

1709989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1709989 is an equidigital number, since it uses as much as digits as its factorization.

1709989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40824, while the sum is 43.

The square root of 1709989 is about 1307.6654771003. The cubic root of 1709989 is about 119.5816217291.

The spelling of 1709989 in words is "one million, seven hundred nine thousand, nine hundred eighty-nine".