5221071665 has 24 divisors (see below), whose sum is σ = 6477884280. Its totient is φ = 4039561728.

The previous prime is 5221071643. The next prime is 5221071683. The reversal of 5221071665 is 5661701225.

It can be written as a sum of positive squares in 12 ways, for example, as 2598544 + 5218473121 = 1612^2 + 72239^2 .

It is not a de Polignac number, because 5221071665 - 2¹⁰ = 5221070641 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1181981 + ... + 1186389.

It is an arithmetic number, because the mean of its divisors is an integer number (269911845).

Almost surely, 2^5221071665 is an apocalyptic number.

It is an amenable number.

5221071665 is a deficient number, since it is larger than the sum of its proper divisors (1256812615).

5221071665 is a wasteful number, since it uses less digits than its factorization.

5221071665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4661 (or 4624 counting only the distinct ones).

The product of its (nonzero) digits is 25200, while the sum is 35.

The square root of 5221071665 is about 72256.9835033265. The cubic root of 5221071665 is about 1734.8151978945.

The spelling of 5221071665 in words is "five billion, two hundred twenty-one million, seventy-one thousand, six hundred sixty-five".