644906024480 has 96 divisors (see below), whose sum is σ = 1537660454400. Its totient is φ = 255581949952.

The previous prime is 644906024447. The next prime is 644906024569. The reversal of 644906024480 is 84420609446.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 63980081 + ... + 63990159.

It is an arithmetic number, because the mean of its divisors is an integer number (16017296400).

Almost surely, 2^644906024480 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 644906024480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (768830227200).

644906024480 is an abundant number, since it is smaller than the sum of its proper divisors (892754429920).

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

644906024480 is a wasteful number, since it uses less digits than its factorization.

644906024480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13746 (or 13738 counting only the distinct ones).

The product of its (nonzero) digits is 1327104, while the sum is 47.

The spelling of 644906024480 in words is "six hundred forty-four billion, nine hundred six million, twenty-four thousand, four hundred eighty".