644133321616603 has 8 divisors (see below), whose sum is σ = 792779472759008. Its totient is φ = 509643946773504.

The previous prime is 644133321616523. The next prime is 644133321616613. The reversal of 644133321616603 is 306616123331446.

It is a happy number.

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 644133321616603 - 2²¹ = 644133319519451 is a prime.

It is not an unprimeable number, because it can be changed into a prime (644133321616613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3539194074726 + ... + 3539194074907.

It is an arithmetic number, because the mean of its divisors is an integer number (99097434094876).

Almost surely, 2^{644133321616603} is an apocalyptic number.

644133321616603 is a deficient number, since it is larger than the sum of its proper divisors (148646151142405).

644133321616603 is a wasteful number, since it uses less digits than its factorization.

644133321616603 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7078388149653.

The product of its (nonzero) digits is 3359232, while the sum is 49.

The spelling of 644133321616603 in words is "six hundred forty-four trillion, one hundred thirty-three billion, three hundred twenty-one million, six hundred sixteen thousand, six hundred three".