6398576640 has 192 divisors, whose sum is σ = 22745923200. Its totient is φ = 1706213376.

The previous prime is 6398576621. The next prime is 6398576641. The reversal of 6398576640 is 466758936.

6398576640 is a `hidden beast` number, since 6 + 3 + 9 + 8 + 576 + 64 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (192).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (6398576641) 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, 264909 + ... + 288051.

It is an arithmetic number, because the mean of its divisors is an integer number (118468350).

Almost surely, 2^6398576640 is an apocalyptic number.

6398576640 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 6398576640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11372961600).

6398576640 is an abundant number, since it is smaller than the sum of its proper divisors (16347346560).

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

6398576640 is a wasteful number, since it uses less digits than its factorization.

6398576640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23179 (or 23153 counting only the distinct ones).

The product of its (nonzero) digits is 6531840, while the sum is 54.

The square root of 6398576640 is about 79991.1035053274. The cubic root of 6398576640 is about 1856.4978846594.

It can be divided in two parts, 63985 and 76640, that added together give a square (140625 = 375²).

The spelling of 6398576640 in words is "six billion, three hundred ninety-eight million, five hundred seventy-six thousand, six hundred forty".