6463391872 has 128 divisors (see below), whose sum is σ = 15516794880. Its totient is φ = 2623104000.

The previous prime is 6463391833. The next prime is 6463391917. The reversal of 6463391872 is 2781933646.

It is a tau number, because it is divible by the number of its divisors (128).

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, 1302997 + ... + 1307947.

It is an arithmetic number, because the mean of its divisors is an integer number (121224960).

Almost surely, 2^6463391872 is an apocalyptic number.

6463391872 is a gapful number since it is divisible by the number (62) 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 6463391872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7758397440).

6463391872 is an abundant number, since it is smaller than the sum of its proper divisors (9053403008).

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

6463391872 is a wasteful number, since it uses less digits than its factorization.

6463391872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5050 (or 5038 counting only the distinct ones).

The product of its digits is 1306368, while the sum is 49.

The square root of 6463391872 is about 80395.2229426600. Note that the first 3 decimals coincide. The cubic root of 6463391872 is about 1862.7453842541.

The spelling of 6463391872 in words is "six billion, four hundred sixty-three million, three hundred ninety-one thousand, eight hundred seventy-two".