644006141 has 8 divisors (see below), whose sum is σ = 687635520. Its totient is φ = 601679232.

The previous prime is 644006137. The next prime is 644006171. The reversal of 644006141 is 141600446.

644006141 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 644006141 - 2² = 644006137 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 644006141.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644006101) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 324596 + ... + 326573.

It is an arithmetic number, because the mean of its divisors is an integer number (85954440).

Almost surely, 2^644006141 is an apocalyptic number.

It is an amenable number.

644006141 is a deficient number, since it is larger than the sum of its proper divisors (43629379).

644006141 is a wasteful number, since it uses less digits than its factorization.

644006141 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 651235.

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 644006141 is about 25377.2760752607. The cubic root of 644006141 is about 863.5682557458.

Adding to 644006141 its reverse (141600446), we get a palindrome (785606587).

The spelling of 644006141 in words is "six hundred forty-four million, six thousand, one hundred forty-one".