1345981685 has 4 divisors (see below), whose sum is σ = 1615178028. Its totient is φ = 1076785344.

The previous prime is 1345981667. The next prime is 1345981709. The reversal of 1345981685 is 5861895431.

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 546110161 + 799871524 = 23369^2 + 28282^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1345981685 is a prime.

It is a Duffinian 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, 134598164 + ... + 134598173.

It is an arithmetic number, because the mean of its divisors is an integer number (403794507).

Almost surely, 2^1345981685 is an apocalyptic number.

It is an amenable number.

1345981685 is a deficient number, since it is larger than the sum of its proper divisors (269196343).

1345981685 is an equidigital number, since it uses as much as digits as its factorization.

1345981685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 269196342.

The product of its digits is 1036800, while the sum is 50.

The square root of 1345981685 is about 36687.6230491974. The cubic root of 1345981685 is about 1104.1117969142. Note that the first 3 decimals are identical.

The spelling of 1345981685 in words is "one billion, three hundred forty-five million, nine hundred eighty-one thousand, six hundred eighty-five".