1331305 has 4 divisors (see below), whose sum is σ = 1597572. Its totient is φ = 1065040.

The previous prime is 1331299. The next prime is 1331327. The reversal of 1331305 is 5031331.

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 817216 + 514089 = 904^2 + 717^2 .

It is not a de Polignac number, because 1331305 - 2¹⁵ = 1298537 is a prime.

It is a Duffinian number.

1331305 is a lucky 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, 133126 + ... + 133135.

It is an arithmetic number, because the mean of its divisors is an integer number (399393).

2^1331305 is an apocalyptic number.

It is an amenable number.

1331305 is a deficient number, since it is larger than the sum of its proper divisors (266267).

1331305 is an equidigital number, since it uses as much as digits as its factorization.

1331305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266266.

The product of its (nonzero) digits is 135, while the sum is 16.

The square root of 1331305 is about 1153.8219100017. The cubic root of 1331305 is about 110.0084015621.

Adding to 1331305 its reverse (5031331), we get a palindrome (6362636).

The spelling of 1331305 in words is "one million, three hundred thirty-one thousand, three hundred five".