6443381880 has 144 divisors (see below), whose sum is σ = 22675961880. Its totient is φ = 1586048256.

The previous prime is 6443381873. The next prime is 6443381887. The reversal of 6443381880 is 881833446.

6443381880 is a `hidden beast` number, since 64 + 433 + 81 + 8 + 80 = 666.

It is an interprime number because it is at equal distance from previous prime (6443381873) and next prime (6443381887).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6443381887) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 7887 + ... + 113793.

Almost surely, 2^6443381880 is an apocalyptic number.

6443381880 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 6443381880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11337980940).

6443381880 is an abundant number, since it is smaller than the sum of its proper divisors (16232580000).

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

6443381880 is a wasteful number, since it uses less digits than its factorization.

6443381880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105950 (or 105930 counting only the distinct ones).

The product of its (nonzero) digits is 442368, while the sum is 45.

The square root of 6443381880 is about 80270.6788310651. The cubic root of 6443381880 is about 1860.8211081538.

The spelling of 6443381880 in words is "six billion, four hundred forty-three million, three hundred eighty-one thousand, eight hundred eighty".