1728349 has 4 divisors (see below), whose sum is σ = 1975264. Its totient is φ = 1481436.

The previous prime is 1728341. The next prime is 1728361. The reversal of 1728349 is 9438271.

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, and also an emirpimes, since its reverse is a distinct semiprime: 9438271 = 1459 ⋅6469.

It is a cyclic number.

It is not a de Polignac number, because 1728349 - 2³ = 1728341 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1728341) 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, 123447 + ... + 123460.

It is an arithmetic number, because the mean of its divisors is an integer number (493816).

2^1728349 is an apocalyptic number.

It is an amenable number.

1728349 is a deficient number, since it is larger than the sum of its proper divisors (246915).

1728349 is an equidigital number, since it uses as much as digits as its factorization.

1728349 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 246914.

The product of its digits is 12096, while the sum is 34.

The square root of 1728349 is about 1314.6668779581. Note that the first 3 decimals coincide. The cubic root of 1728349 is about 120.0080781599.

The spelling of 1728349 in words is "one million, seven hundred twenty-eight thousand, three hundred forty-nine".