6649644456 has 192 divisors, whose sum is σ = 22987036800. Its totient is φ = 1753705728.

The previous prime is 6649644437. The next prime is 6649644457. The reversal of 6649644456 is 6544469466.

6649644456 is a `hidden beast` number, since 6 + 64 + 96 + 44 + 456 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (6649644457) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 158110 + ... + 195698.

It is an arithmetic number, because the mean of its divisors is an integer number (119724150).

Almost surely, 2^6649644456 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 6649644456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11493518400).

6649644456 is an abundant number, since it is smaller than the sum of its proper divisors (16337392344).

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

6649644456 is a wasteful number, since it uses less digits than its factorization.

6649644456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37630 (or 37614 counting only the distinct ones).

The product of its digits is 14929920, while the sum is 54.

The square root of 6649644456 is about 81545.3521422282. The cubic root of 6649644456 is about 1880.4688411194.

The spelling of 6649644456 in words is "six billion, six hundred forty-nine million, six hundred forty-four thousand, four hundred fifty-six".