1664373 has 4 divisors (see below), whose sum is σ = 2219168. Its totient is φ = 1109580.

The previous prime is 1664353. The next prime is 1664387. The reversal of 1664373 is 3734661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1664373 - 2⁹ = 1663861 is a prime.

It is a D-number.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1664373.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1664353) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 277393 + ... + 277398.

It is an arithmetic number, because the mean of its divisors is an integer number (554792).

2^1664373 is an apocalyptic number.

It is an amenable number.

1664373 is a deficient number, since it is larger than the sum of its proper divisors (554795).

1664373 is an equidigital number, since it uses as much as digits as its factorization.

1664373 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 554794.

The product of its digits is 9072, while the sum is 30.

The square root of 1664373 is about 1290.1058096141. The cubic root of 1664373 is about 118.5086963299.

The spelling of 1664373 in words is "one million, six hundred sixty-four thousand, three hundred seventy-three".