644002160240 has 40 divisors (see below), whose sum is σ = 1504829205600. Its totient is φ = 256306381056.

The previous prime is 644002160233. The next prime is 644002160299. The reversal of 644002160240 is 42061200446.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 20210279 + ... + 20242118.

It is an arithmetic number, because the mean of its divisors is an integer number (37620730140).

Almost surely, 2^644002160240 is an apocalyptic number.

It is an amenable number.

644002160240 is an abundant number, since it is smaller than the sum of its proper divisors (860827045360).

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

644002160240 is a wasteful number, since it uses less digits than its factorization.

644002160240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40452609 (or 40452603 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 29.

Adding to 644002160240 its reverse (42061200446), we get a palindrome (686063360686).

The spelling of 644002160240 in words is "six hundred forty-four billion, two million, one hundred sixty thousand, two hundred forty".