1311729 has 4 divisors (see below), whose sum is σ = 1748976. Its totient is φ = 874484.

The previous prime is 1311721. The next prime is 1311733. The reversal of 1311729 is 9271131.

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 a cyclic number.

It is not a de Polignac number, because 1311729 - 2³ = 1311721 is a prime.

It is a D-number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1311699 and 1311708.

It is not an unprimeable number, because it can be changed into a prime (1311721) 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, 218619 + ... + 218624.

It is an arithmetic number, because the mean of its divisors is an integer number (437244).

2^1311729 is an apocalyptic number.

It is an amenable number.

1311729 is a deficient number, since it is larger than the sum of its proper divisors (437247).

1311729 is an equidigital number, since it uses as much as digits as its factorization.

1311729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 437246.

The product of its digits is 378, while the sum is 24.

The square root of 1311729 is about 1145.3073823214. The cubic root of 1311729 is about 109.4665355090.

The spelling of 1311729 in words is "one million, three hundred eleven thousand, seven hundred twenty-nine".