6447547165 has 4 divisors (see below), whose sum is σ = 7737056604. Its totient is φ = 5158037728.

The previous prime is 6447547163. The next prime is 6447547187. The reversal of 6447547165 is 5617457446.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5617457446 = 2 ⋅2808728723.

It can be written as a sum of positive squares in 2 ways, for example, as 4339910884 + 2107636281 = 65878^2 + 45909^2 .

It is a cyclic number.

It is not a de Polignac number, because 6447547165 - 2¹ = 6447547163 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6447547163) 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, 644754712 + ... + 644754721.

It is an arithmetic number, because the mean of its divisors is an integer number (1934264151).

Almost surely, 2^6447547165 is an apocalyptic number.

It is an amenable number.

6447547165 is a deficient number, since it is larger than the sum of its proper divisors (1289509439).

6447547165 is a wasteful number, since it uses less digits than its factorization.

6447547165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1289509438.

The product of its digits is 2822400, while the sum is 49.

The square root of 6447547165 is about 80296.6198852729. The cubic root of 6447547165 is about 1861.2219939428.

The spelling of 6447547165 in words is "six billion, four hundred forty-seven million, five hundred forty-seven thousand, one hundred sixty-five".