6645086020 has 24 divisors (see below), whose sum is σ = 13956899544. Its totient is φ = 2657611776.

The previous prime is 6645085981. The next prime is 6645086093. The reversal of 6645086020 is 206805466.

It can be written as a sum of positive squares in 4 ways, for example, as 371178756 + 6273907264 = 19266^2 + 79208^2 .

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, 123174 + ... + 168706.

It is an arithmetic number, because the mean of its divisors is an integer number (581537481).

Almost surely, 2^6645086020 is an apocalyptic number.

It is an amenable number.

6645086020 is an abundant number, since it is smaller than the sum of its proper divisors (7311813524).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6645086020 is a wasteful number, since it uses less digits than its factorization.

6645086020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52839 (or 52837 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 37.

The square root of 6645086020 is about 81517.3970389143. The cubic root of 6645086020 is about 1880.0390458919.

The spelling of 6645086020 in words is "six billion, six hundred forty-five million, eighty-six thousand, twenty".