644263056041 has 8 divisors (see below), whose sum is σ = 702882805824. Its totient is φ = 585651703120.

The previous prime is 644263056013. The next prime is 644263056109. The reversal of 644263056041 is 140650362446.

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

It is not a de Polignac number, because 644263056041 - 2¹⁴ = 644263039657 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 644263056041.

It is not an unprimeable number, because it can be changed into a prime (644263256041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1938245 + ... + 2246178.

It is an arithmetic number, because the mean of its divisors is an integer number (87860350728).

Almost surely, 2^644263056041 is an apocalyptic number.

It is an amenable number.

644263056041 is a deficient number, since it is larger than the sum of its proper divisors (58619749783).

644263056041 is a wasteful number, since it uses less digits than its factorization.

644263056041 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4198431.

The product of its (nonzero) digits is 414720, while the sum is 41.

The spelling of 644263056041 in words is "six hundred forty-four billion, two hundred sixty-three million, fifty-six thousand, forty-one".