1285729 has 4 divisors (see below), whose sum is σ = 1288980. Its totient is φ = 1282480.

The previous prime is 1285717. The next prime is 1285741. The reversal of 1285729 is 9275821.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (1285717) and next prime (1285741).

It can be written as a sum of positive squares in 2 ways, for example, as 608400 + 677329 = 780^2 + 823^2 .

It is a cyclic number.

It is not a de Polignac number, because 1285729 - 2¹⁹ = 761441 is a prime.

It is a super-2 number, since 2×1285729² = 3306198122882, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 14.

It is a junction number, because it is equal to n+sod(n) for n = 1285694 and 1285703.

It is not an unprimeable number, because it can be changed into a prime (1285759) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 934 + ... + 1855.

It is an arithmetic number, because the mean of its divisors is an integer number (322245).

2^1285729 is an apocalyptic number.

It is an amenable number.

1285729 is a deficient number, since it is larger than the sum of its proper divisors (3251).

1285729 is an equidigital number, since it uses as much as digits as its factorization.

1285729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3250.

The product of its digits is 10080, while the sum is 34.

The square root of 1285729 is about 1133.8999073992. The cubic root of 1285729 is about 108.7384521142.

The spelling of 1285729 in words is "one million, two hundred eighty-five thousand, seven hundred twenty-nine".