1320605345 has 8 divisors (see below), whose sum is σ = 1587658920. Its totient is φ = 1054529280.

The previous prime is 1320605311. The next prime is 1320605347. The reversal of 1320605345 is 5435060231.

It can be written as a sum of positive squares in 4 ways, for example, as 372026944 + 948578401 = 19288^2 + 30799^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-1320605345 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1320605347) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 241400 + ... + 246809.

It is an arithmetic number, because the mean of its divisors is an integer number (198457365).

Almost surely, 2^1320605345 is an apocalyptic number.

It is an amenable number.

1320605345 is a deficient number, since it is larger than the sum of its proper divisors (267053575).

1320605345 is an equidigital number, since it uses as much as digits as its factorization.

1320605345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 488755.

The product of its (nonzero) digits is 10800, while the sum is 29.

The square root of 1320605345 is about 36340.1340806552. The cubic root of 1320605345 is about 1097.1289717395.

Adding to 1320605345 its reverse (5435060231), we get a palindrome (6755665576).

The spelling of 1320605345 in words is "one billion, three hundred twenty million, six hundred five thousand, three hundred forty-five".