1329805 has 4 divisors (see below), whose sum is σ = 1595772. Its totient is φ = 1063840.

The previous prime is 1329799. The next prime is 1329847. The reversal of 1329805 is 5089231.

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

It can be written as a sum of positive squares in 2 ways, for example, as 373321 + 956484 = 611^2 + 978^2 .

It is not a de Polignac number, because 1329805 - 2¹⁹ = 805517 is a prime.

It is a Duffinian number.

1329805 is a lucky number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 132976 + ... + 132985.

It is an arithmetic number, because the mean of its divisors is an integer number (398943).

2^1329805 is an apocalyptic number.

It is an amenable number.

1329805 is a deficient number, since it is larger than the sum of its proper divisors (265967).

1329805 is an equidigital number, since it uses as much as digits as its factorization.

1329805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 265966.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 1329805 is about 1153.1717131460. The cubic root of 1329805 is about 109.9670700328.

The spelling of 1329805 in words is "one million, three hundred twenty-nine thousand, eight hundred five".