6642800640 has 432 divisors, whose sum is σ = 26799776640. Its totient is φ = 1517322240.

The previous prime is 6642800617. The next prime is 6642800707. The reversal of 6642800640 is 460082466.

It is a happy number.

6642800640 is a `hidden beast` number, since 6 + 6 + 4 + 2 + 8 + 0 + 0 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 6642800595 and 6642800604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 4515105 + ... + 4516575.

It is an arithmetic number, because the mean of its divisors is an integer number (62036520).

Almost surely, 2^6642800640 is an apocalyptic number.

6642800640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6642800640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13399888320).

6642800640 is an abundant number, since it is smaller than the sum of its proper divisors (20156976000).

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

6642800640 is a wasteful number, since it uses less digits than its factorization.

6642800640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1518 (or 1488 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 36.

The square root of 6642800640 is about 81503.3780895001. The cubic root of 6642800640 is about 1879.8234933127.

The spelling of 6642800640 in words is "six billion, six hundred forty-two million, eight hundred thousand, six hundred forty".