1966009 has 2 divisors, whose sum is σ = 1966010. Its totient is φ = 1966008.

The previous prime is 1966007. The next prime is 1966031. The reversal of 1966009 is 9006691.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1951609 + 14400 = 1397^2 + 120^2 .

It is a cyclic number.

It is not a de Polignac number, because 1966009 - 2¹ = 1966007 is a prime.

Together with 1966007, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1966007) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 983004 + 983005.

It is an arithmetic number, because the mean of its divisors is an integer number (983005).

2^1966009 is an apocalyptic number.

It is an amenable number.

1966009 is a deficient number, since it is larger than the sum of its proper divisors (1).

1966009 is an equidigital number, since it uses as much as digits as its factorization.

1966009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2916, while the sum is 31.

The square root of 1966009 is about 1402.1444290800. The cubic root of 1966009 is about 125.2742564936.

The spelling of 1966009 in words is "one million, nine hundred sixty-six thousand, nine".