1306645 has 4 divisors (see below), whose sum is σ = 1567980. Its totient is φ = 1045312.

The previous prime is 1306633. The next prime is 1306661. The reversal of 1306645 is 5466031.

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 485809 + 820836 = 697^2 + 906^2 .

It is a cyclic number.

It is not a de Polignac number, because 1306645 - 2⁷ = 1306517 is a prime.

1306645 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, 130660 + ... + 130669.

It is an arithmetic number, because the mean of its divisors is an integer number (391995).

2^1306645 is an apocalyptic number.

It is an amenable number.

1306645 is a deficient number, since it is larger than the sum of its proper divisors (261335).

1306645 is an equidigital number, since it uses as much as digits as its factorization.

1306645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 261334.

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 1306645 is about 1143.0857360671. The cubic root of 1306645 is about 109.3249289181.

The spelling of 1306645 in words is "one million, three hundred six thousand, six hundred forty-five".