644050491336 has 192 divisors, whose sum is σ = 2044769126400. Its totient is φ = 179336332800.

The previous prime is 644050491319. The next prime is 644050491347. The reversal of 644050491336 is 633194050446.

644050491336 is a `hidden beast` number, since 6 + 4 + 4 + 0 + 504 + 9 + 133 + 6 = 666.

644050491336 is digitally balanced in base 7, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×644050491336² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 644050491291 and 644050491300.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3255001 + ... + 3447191.

It is an arithmetic number, because the mean of its divisors is an integer number (10649839200).

Almost surely, 2^644050491336 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 644050491336, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1022384563200).

644050491336 is an abundant number, since it is smaller than the sum of its proper divisors (1400718635064).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

644050491336 is a wasteful number, since it uses less digits than its factorization.

644050491336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 192380 (or 192373 counting only the distinct ones).

The product of its (nonzero) digits is 933120, while the sum is 45.

The spelling of 644050491336 in words is "six hundred forty-four billion, fifty million, four hundred ninety-one thousand, three hundred thirty-six".