8639660521 has 8 divisors (see below), whose sum is σ = 8709986304. Its totient is φ = 8569370880.

The previous prime is 8639660503. The next prime is 8639660531. The reversal of 8639660521 is 1250669368.

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 8639660521 - 2¹⁵ = 8639627753 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8639660501) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 684756 + ... + 697258.

It is an arithmetic number, because the mean of its divisors is an integer number (1088748288).

Almost surely, 2^8639660521 is an apocalyptic number.

It is an amenable number.

8639660521 is a deficient number, since it is larger than the sum of its proper divisors (70325783).

8639660521 is a wasteful number, since it uses less digits than its factorization.

8639660521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18071.

The product of its (nonzero) digits is 466560, while the sum is 46.

The square root of 8639660521 is about 92949.7741847714. The cubic root of 8639660521 is about 2051.9442606172.

The spelling of 8639660521 in words is "eight billion, six hundred thirty-nine million, six hundred sixty thousand, five hundred twenty-one".