644566046003 has 16 divisors (see below), whose sum is σ = 740320800000. Its totient is φ = 555016704480.

The previous prime is 644566045987. The next prime is 644566046023. The reversal of 644566046003 is 300640665446.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 644566046003 - 2⁴ = 644566045987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (644566046023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 736325 + ... + 1353257.

It is an arithmetic number, because the mean of its divisors is an integer number (46270050000).

Almost surely, 2^644566046003 is an apocalyptic number.

644566046003 is a deficient number, since it is larger than the sum of its proper divisors (95754753997).

644566046003 is a wasteful number, since it uses less digits than its factorization.

644566046003 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 621962.

The product of its (nonzero) digits is 1244160, while the sum is 44.

The spelling of 644566046003 in words is "six hundred forty-four billion, five hundred sixty-six million, forty-six thousand, three".