6443701840 has 80 divisors (see below), whose sum is σ = 15377082768. Its totient is φ = 2510163968.

The previous prime is 6443701807. The next prime is 6443701841. The reversal of 6443701840 is 481073446.

It can be written as a sum of positive squares in 8 ways, for example, as 457275456 + 5986426384 = 21384^2 + 77372^2 .

It is a tau number, because it is divible by the number of its divisors (80).

It is a self number, because there is not a number n which added to its sum of digits gives 6443701840.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6443701841) 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, 575334 + ... + 586426.

Almost surely, 2^6443701840 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 6443701840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7688541384).

6443701840 is an abundant number, since it is smaller than the sum of its proper divisors (8933380928).

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

6443701840 is a wasteful number, since it uses less digits than its factorization.

6443701840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11296 (or 11290 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 37.

The square root of 6443701840 is about 80272.6718130149. The cubic root of 6443701840 is about 1860.8519086702.

The spelling of 6443701840 in words is "six billion, four hundred forty-three million, seven hundred one thousand, eight hundred forty".