6640567345 has 4 divisors (see below), whose sum is σ = 7968680820. Its totient is φ = 5312453872.

The previous prime is 6640567343. The next prime is 6640567391. The reversal of 6640567345 is 5437650466.

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 2416607281 + 4223960064 = 49159^2 + 64992^2 .

It is a cyclic number.

It is not a de Polignac number, because 6640567345 - 2¹ = 6640567343 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 6640567295 and 6640567304.

It is not an unprimeable number, because it can be changed into a prime (6640567343) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 664056730 + ... + 664056739.

It is an arithmetic number, because the mean of its divisors is an integer number (1992170205).

Almost surely, 2^6640567345 is an apocalyptic number.

It is an amenable number.

6640567345 is a deficient number, since it is larger than the sum of its proper divisors (1328113475).

6640567345 is a wasteful number, since it uses less digits than its factorization.

6640567345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1328113474.

The product of its (nonzero) digits is 1814400, while the sum is 46.

The square root of 6640567345 is about 81489.6763093338. The cubic root of 6640567345 is about 1879.6128055221.

The spelling of 6640567345 in words is "six billion, six hundred forty million, five hundred sixty-seven thousand, three hundred forty-five".