4021530665 has 8 divisors (see below), whose sum is σ = 4856575560. Its totient is φ = 3196732032.

The previous prime is 4021530647. The next prime is 4021530679. The reversal of 4021530665 is 5660351204.

It can be written as a sum of positive squares in 4 ways, for example, as 858255616 + 3163275049 = 29296^2 + 56243^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 4021530665 - 2¹⁰ = 4021529641 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2560700 + ... + 2562269.

It is an arithmetic number, because the mean of its divisors is an integer number (607071945).

Almost surely, 2^4021530665 is an apocalyptic number.

It is an amenable number.

4021530665 is a deficient number, since it is larger than the sum of its proper divisors (835044895).

4021530665 is a wasteful number, since it uses less digits than its factorization.

4021530665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5123131.

The product of its (nonzero) digits is 21600, while the sum is 32.

The square root of 4021530665 is about 63415.5396176678. The cubic root of 4021530665 is about 1590.2441070039.

Adding to 4021530665 its reverse (5660351204), we get a palindrome (9681881869).

The spelling of 4021530665 in words is "four billion, twenty-one million, five hundred thirty thousand, six hundred sixty-five".