644374811203 has 6 divisors (see below), whose sum is σ = 684508882796. Its totient is φ = 606470410272.

The previous prime is 644374811183. The next prime is 644374811221. The reversal of 644374811203 is 302118473446.

It is not a de Polignac number, because 644374811203 - 2¹³ = 644374803011 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 644374811203.

It is not an unprimeable number, because it can be changed into a prime (644374811603) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 1114835025 + ... + 1114835602.

Almost surely, 2^644374811203 is an apocalyptic number.

644374811203 is a deficient number, since it is larger than the sum of its proper divisors (40134071593).

644374811203 is a wasteful number, since it uses less digits than its factorization.

644374811203 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2229670661 (or 2229670644 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 43.

The spelling of 644374811203 in words is "six hundred forty-four billion, three hundred seventy-four million, eight hundred eleven thousand, two hundred three".