6399977760 has 288 divisors, whose sum is σ = 25227925632. Its totient is φ = 1460183040.

The previous prime is 6399977747. The next prime is 6399977761. The reversal of 6399977760 is 677799936.

It is a tau number, because it is divible by the number of its divisors (288).

It is not an unprimeable number, because it can be changed into a prime (6399977761) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 257397 + ... + 281163.

It is an arithmetic number, because the mean of its divisors is an integer number (87596964).

Almost surely, 2^6399977760 is an apocalyptic number.

6399977760 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 6399977760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12613962816).

6399977760 is an abundant number, since it is smaller than the sum of its proper divisors (18827947872).

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

6399977760 is a wasteful number, since it uses less digits than its factorization.

6399977760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23816 (or 23805 counting only the distinct ones).

The product of its (nonzero) digits is 27005076, while the sum is 63.

The square root of 6399977760 is about 79999.8609998792. The cubic root of 6399977760 is about 1856.6333828398.

The spelling of 6399977760 in words is "six billion, three hundred ninety-nine million, nine hundred seventy-seven thousand, seven hundred sixty".