844736640 has 512 divisors, whose sum is σ = 3214909440. Its totient is φ = 186531840.

The previous prime is 844736611. The next prime is 844736699. The reversal of 844736640 is 46637448.

It is a junction number, because it is equal to n+sod(n) for n = 844736592 and 844736601.

It is an unprimeable number.

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 63 ways as a sum of consecutive naturals, for example, 17973097 + ... + 17973143.

It is an arithmetic number, because the mean of its divisors is an integer number (6279120).

Almost surely, 2^844736640 is an apocalyptic number.

844736640 is a gapful number since it is divisible by the number (80) 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 844736640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1607454720).

844736640 is an abundant number, since it is smaller than the sum of its proper divisors (2370172800).

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

844736640 is a wasteful number, since it uses less digits than its factorization.

844736640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140 (or 128 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 42.

The square root of 844736640 is about 29064.3534247710. The cubic root of 844736640 is about 945.3089664681.

The spelling of 844736640 in words is "eight hundred forty-four million, seven hundred thirty-six thousand, six hundred forty".