6445813872 has 40 divisors (see below), whose sum is σ = 17005982976. Its totient is φ = 2102888896.

The previous prime is 6445813841. The next prime is 6445813873. The reversal of 6445813872 is 2783185446.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6445813873) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1426338 + ... + 1430849.

Almost surely, 2^6445813872 is an apocalyptic number.

It is an amenable number.

6445813872 is an abundant number, since it is smaller than the sum of its proper divisors (10560169104).

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

6445813872 is a wasteful number, since it uses less digits than its factorization.

6445813872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2857245 (or 2857239 counting only the distinct ones).

The product of its digits is 1290240, while the sum is 48.

The square root of 6445813872 is about 80285.8260965159. The cubic root of 6445813872 is about 1861.0551949984.

The spelling of 6445813872 in words is "six billion, four hundred forty-five million, eight hundred thirteen thousand, eight hundred seventy-two".