6518970665 has 4 divisors (see below), whose sum is σ = 7822764804. Its totient is φ = 5215176528.

The previous prime is 6518970659. The next prime is 6518970677. The reversal of 6518970665 is 5660798156.

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 1168340761 + 5350629904 = 34181^2 + 73148^2 .

It is a cyclic number.

It is not a de Polignac number, because 6518970665 - 2⁴ = 6518970649 is a prime.

It is a super-2 number, since 2×6518970665² = 84993957062261084450, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon 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, 651897062 + ... + 651897071.

It is an arithmetic number, because the mean of its divisors is an integer number (1955691201).

Almost surely, 2^6518970665 is an apocalyptic number.

It is an amenable number.

6518970665 is a deficient number, since it is larger than the sum of its proper divisors (1303794139).

6518970665 is a wasteful number, since it uses less digits than its factorization.

6518970665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1303794138.

The product of its (nonzero) digits is 2721600, while the sum is 53.

The square root of 6518970665 is about 80740.1428348997. The cubic root of 6518970665 is about 1868.0694103096.

The spelling of 6518970665 in words is "six billion, five hundred eighteen million, nine hundred seventy thousand, six hundred sixty-five".