2640647568 has 80 divisors (see below), whose sum is σ = 7357306880. Its totient is φ = 811302912.

The previous prime is 2640647563. The next prime is 2640647651. The reversal of 2640647568 is 8657460462.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is not an unprimeable number, because it can be changed into a prime (2640647563) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 477105 + ... + 482607.

It is an arithmetic number, because the mean of its divisors is an integer number (91966336).

Almost surely, 2^2640647568 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 2640647568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3678653440).

2640647568 is an abundant number, since it is smaller than the sum of its proper divisors (4716659312).

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

2640647568 is a wasteful number, since it uses less digits than its factorization.

2640647568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6296 (or 6290 counting only the distinct ones).

The product of its (nonzero) digits is 1935360, while the sum is 48.

The square root of 2640647568 is about 51387.2315658277. The cubic root of 2640647568 is about 1382.1976410303.

The spelling of 2640647568 in words is "two billion, six hundred forty million, six hundred forty-seven thousand, five hundred sixty-eight".