6459987840 has 256 divisors, whose sum is σ = 22037875200. Its totient is φ = 1604689920.

The previous prime is 6459987823. The next prime is 6459987841. The reversal of 6459987840 is 487899546.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6459987841) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2223829 + ... + 2226731.

It is an arithmetic number, because the mean of its divisors is an integer number (86085450).

Almost surely, 2^6459987840 is an apocalyptic number.

6459987840 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 6459987840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11018937600).

6459987840 is an abundant number, since it is smaller than the sum of its proper divisors (15577887360).

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

6459987840 is a wasteful number, since it uses less digits than its factorization.

6459987840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3005 (or 2993 counting only the distinct ones).

The product of its (nonzero) digits is 17418240, while the sum is 60.

The square root of 6459987840 is about 80374.0495433694. The cubic root of 6459987840 is about 1862.4183135503.

The spelling of 6459987840 in words is "six billion, four hundred fifty-nine million, nine hundred eighty-seven thousand, eight hundred forty".