1728361 has 2 divisors, whose sum is σ = 1728362. Its totient is φ = 1728360.

The previous prime is 1728341. The next prime is 1728403. The reversal of 1728361 is 1638271.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 891136 + 837225 = 944^2 + 915^2 .

It is a cyclic number.

It is not a de Polignac number, because 1728361 - 2⁵ = 1728329 is a prime.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (1728341) 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 as a sum of consecutive naturals, namely, 864180 + 864181.

It is an arithmetic number, because the mean of its divisors is an integer number (864181).

2^1728361 is an apocalyptic number.

It is an amenable number.

1728361 is a deficient number, since it is larger than the sum of its proper divisors (1).

1728361 is an equidigital number, since it uses as much as digits as its factorization.

1728361 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2016, while the sum is 28.

The square root of 1728361 is about 1314.6714418439. The cubic root of 1728361 is about 120.0083558996.

The spelling of 1728361 in words is "one million, seven hundred twenty-eight thousand, three hundred sixty-one".