6560621640 has 192 divisors, whose sum is σ = 22650366960. Its totient is φ = 1641185280.

The previous prime is 6560621593. The next prime is 6560621651. The reversal of 6560621640 is 461260656.

It is a happy number.

6560621640 is a `hidden beast` number, since 6 + 5 + 6 + 0 + 6 + 2 + 1 + 640 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 1442936196 + 5117685444 = 37986^2 + 71538^2 .

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 = 6560621595 and 6560621604.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2060850 + ... + 2064030.

Almost surely, 2^6560621640 is an apocalyptic number.

6560621640 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 6560621640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11325183480).

6560621640 is an abundant number, since it is smaller than the sum of its proper divisors (16089745320).

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

6560621640 is a wasteful number, since it uses less digits than its factorization.

6560621640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3552 (or 3545 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The square root of 6560621640 is about 80997.6644107717. The cubic root of 6560621640 is about 1872.0394537488.

The spelling of 6560621640 in words is "six billion, five hundred sixty million, six hundred twenty-one thousand, six hundred forty".