6440672616 has 128 divisors (see below), whose sum is σ = 19110470400. Its totient is φ = 1770577920.

The previous prime is 6440672599. The next prime is 6440672653. The reversal of 6440672616 is 6162760446.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 496420 + ... + 509228.

It is an arithmetic number, because the mean of its divisors is an integer number (149300550).

Almost surely, 2^6440672616 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 6440672616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9555235200).

6440672616 is an abundant number, since it is smaller than the sum of its proper divisors (12669797784).

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

6440672616 is a wasteful number, since it uses less digits than its factorization.

6440672616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12939 (or 12935 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 42.

The square root of 6440672616 is about 80253.8012557661. The cubic root of 6440672616 is about 1860.5602636420.

The spelling of 6440672616 in words is "six billion, four hundred forty million, six hundred seventy-two thousand, six hundred sixteen".