1664439 has 8 divisors (see below), whose sum is σ = 2536320. Its totient is φ = 951096.

The previous prime is 1664437. The next prime is 1664447. The reversal of 1664439 is 9344661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1664439 - 2¹ = 1664437 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1664431) 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 7 ways as a sum of consecutive naturals, for example, 39609 + ... + 39650.

It is an arithmetic number, because the mean of its divisors is an integer number (317040).

2^1664439 is an apocalyptic number.

1664439 is a deficient number, since it is larger than the sum of its proper divisors (871881).

1664439 is an equidigital number, since it uses as much as digits as its factorization.

1664439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79269.

The product of its digits is 15552, while the sum is 33.

The square root of 1664439 is about 1290.1313886578. The cubic root of 1664439 is about 118.5102627797.

The spelling of 1664439 in words is "one million, six hundred sixty-four thousand, four hundred thirty-nine".