6400638260 has 24 divisors (see below), whose sum is σ = 14025747456. Its totient is φ = 2448939680.

The previous prime is 6400638259. The next prime is 6400638311. The reversal of 6400638260 is 628360046.

It is a self number, because there is not a number n which added to its sum of digits gives 6400638260.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6956756 + ... + 6957675.

It is an arithmetic number, because the mean of its divisors is an integer number (584406144).

Almost surely, 2^6400638260 is an apocalyptic number.

It is an amenable number.

6400638260 is an abundant number, since it is smaller than the sum of its proper divisors (7625109196).

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

6400638260 is a wasteful number, since it uses less digits than its factorization.

6400638260 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13914463 (or 13914461 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 35.

The square root of 6400638260 is about 80003.9890255480. The cubic root of 6400638260 is about 1856.6972509870.

The spelling of 6400638260 in words is "six billion, four hundred million, six hundred thirty-eight thousand, two hundred sixty".