6400260640 has 96 divisors (see below), whose sum is σ = 16160425344. Its totient is φ = 2386882560.

The previous prime is 6400260613. The next prime is 6400260661. The reversal of 6400260640 is 460620046.

It is a junction number, because it is equal to n+sod(n) for n = 6400260599 and 6400260608.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 280045 + ... + 302035.

It is an arithmetic number, because the mean of its divisors is an integer number (168337764).

Almost surely, 2^6400260640 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 6400260640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8080212672).

6400260640 is an abundant number, since it is smaller than the sum of its proper divisors (9760164704).

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

6400260640 is a wasteful number, since it uses less digits than its factorization.

6400260640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22130 (or 22122 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 28.

The square root of 6400260640 is about 80001.6289834151. The cubic root of 6400260640 is about 1856.6607369303.

Adding to 6400260640 its reverse (460620046), we get a palindrome (6860880686).

It can be divided in two parts, 6400260 and 640, that added together give a square (6400900 = 2530²).

The spelling of 6400260640 in words is "six billion, four hundred million, two hundred sixty thousand, six hundred forty".