1729729 has 4 divisors (see below), whose sum is σ = 1734484. Its totient is φ = 1724976.

The previous prime is 1729727. The next prime is 1729747. The reversal of 1729729 is 9279271.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9279271 = 43 ⋅215797.

It can be written as a sum of positive squares in 2 ways, for example, as 1557504 + 172225 = 1248^2 + 415^2 .

It is a 3-Lehmer number, since φ(1729729) divides (1729729-1)³.

It is a cyclic number.

It is not a de Polignac number, because 1729729 - 2¹ = 1729727 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1729723) 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, 1782 + ... + 2575.

It is an arithmetic number, because the mean of its divisors is an integer number (433621).

2^1729729 is an apocalyptic number.

It is an amenable number.

1729729 is a deficient number, since it is larger than the sum of its proper divisors (4755).

1729729 is an equidigital number, since it uses as much as digits as its factorization.

1729729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4754.

The product of its digits is 15876, while the sum is 37.

The square root of 1729729 is about 1315.1916210195. The cubic root of 1729729 is about 120.0400098068.

The spelling of 1729729 in words is "one million, seven hundred twenty-nine thousand, seven hundred twenty-nine".