6440067844 has 120 divisors (see below), whose sum is σ = 13773211648. Its totient is φ = 2631605760.

The previous prime is 6440067833. The next prime is 6440067847. The reversal of 6440067844 is 4487600446.

It is a self number, because there is not a number n which added to its sum of digits gives 6440067844.

It is not an unprimeable number, because it can be changed into a prime (6440067847) 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 39 ways as a sum of consecutive naturals, for example, 28879117 + ... + 28879339.

Almost surely, 2^6440067844 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 6440067844, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6886605824).

6440067844 is an abundant number, since it is smaller than the sum of its proper divisors (7333143804).

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

6440067844 is a wasteful number, since it uses less digits than its factorization.

6440067844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 383 (or 360 counting only the distinct ones).

The product of its (nonzero) digits is 516096, while the sum is 43.

The square root of 6440067844 is about 80250.0332959432. The cubic root of 6440067844 is about 1860.5020269723.

The spelling of 6440067844 in words is "six billion, four hundred forty million, sixty-seven thousand, eight hundred forty-four".