6444487880 has 64 divisors (see below), whose sum is σ = 15017022000. Its totient is φ = 2486098944.

The previous prime is 6444487879. The next prime is 6444487901. The reversal of 6444487880 is 887844446.

It can be written as a sum of positive squares in 8 ways, for example, as 2605694116 + 3838793764 = 51046^2 + 61958^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1237442 + ... + 1242638.

Almost surely, 2^6444487880 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 6444487880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7508511000).

6444487880 is an abundant number, since it is smaller than the sum of its proper divisors (8572534120).

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

6444487880 is a wasteful number, since it uses less digits than its factorization.

6444487880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6306 (or 6302 counting only the distinct ones).

The product of its (nonzero) digits is 5505024, while the sum is 53.

The square root of 6444487880 is about 80277.5677259843. The cubic root of 6444487880 is about 1860.9275714180.

The spelling of 6444487880 in words is "six billion, four hundred forty-four million, four hundred eighty-seven thousand, eight hundred eighty".