644003612219 has 16 divisors (see below), whose sum is σ = 758374168320. Its totient is φ = 540692681760.

The previous prime is 644003612177. The next prime is 644003612281. The reversal of 644003612219 is 912216300446.

It is not a de Polignac number, because 644003612219 - 2³² = 639708644923 is a prime.

It is a super-2 number, since 2×644003612219² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (644003611219) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 43880057 + ... + 43894730.

It is an arithmetic number, because the mean of its divisors is an integer number (47398385520).

Almost surely, 2^644003612219 is an apocalyptic number.

644003612219 is a deficient number, since it is larger than the sum of its proper divisors (114370556101).

644003612219 is a wasteful number, since it uses less digits than its factorization.

644003612219 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87774850.

The product of its (nonzero) digits is 62208, while the sum is 38.

The spelling of 644003612219 in words is "six hundred forty-four billion, three million, six hundred twelve thousand, two hundred nineteen".