6620664544 has 96 divisors (see below), whose sum is σ = 14604226560. Its totient is φ = 2933798400.

The previous prime is 6620664539. The next prime is 6620664553. The reversal of 6620664544 is 4454660266.

It is a self number, because there is not a number n which added to its sum of digits gives 6620664544.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1687417 + ... + 1691335.

It is an arithmetic number, because the mean of its divisors is an integer number (152127360).

Almost surely, 2^6620664544 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6620664544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7302113280).

6620664544 is an abundant number, since it is smaller than the sum of its proper divisors (7983562016).

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

6620664544 is a wasteful number, since it uses less digits than its factorization.

6620664544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4104 (or 4096 counting only the distinct ones).

The product of its (nonzero) digits is 829440, while the sum is 43.

The square root of 6620664544 is about 81367.4661274394. The cubic root of 6620664544 is about 1877.7330968515.

The spelling of 6620664544 in words is "six billion, six hundred twenty million, six hundred sixty-four thousand, five hundred forty-four".