1664959 has 2 divisors, whose sum is σ = 1664960. Its totient is φ = 1664958.

The previous prime is 1664941. The next prime is 1664987. The reversal of 1664959 is 9594661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1664959 - 2⁹ = 1664447 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1664909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 832479 + 832480.

It is an arithmetic number, because the mean of its divisors is an integer number (832480).

2^1664959 is an apocalyptic number.

1664959 is a deficient number, since it is larger than the sum of its proper divisors (1).

1664959 is an equidigital number, since it uses as much as digits as its factorization.

1664959 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 58320, while the sum is 40.

The square root of 1664959 is about 1290.3329027813. The cubic root of 1664959 is about 118.5226030578.

The spelling of 1664959 in words is "one million, six hundred sixty-four thousand, nine hundred fifty-nine".