644050447 has 8 divisors (see below), whose sum is σ = 658213056. Its totient is φ = 629907072.

The previous prime is 644050403. The next prime is 644050483. The reversal of 644050447 is 744050446.

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 644050447 - 2¹¹ = 644048399 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644053447) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 78483 + ... + 86299.

It is an arithmetic number, because the mean of its divisors is an integer number (82276632).

Almost surely, 2^644050447 is an apocalyptic number.

644050447 is a deficient number, since it is larger than the sum of its proper divisors (14162609).

644050447 is a wasteful number, since it uses less digits than its factorization.

644050447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9617.

The product of its (nonzero) digits is 53760, while the sum is 34.

The square root of 644050447 is about 25378.1490065765. The cubic root of 644050447 is about 863.5880590651.

Subtracting 644050447 from its reverse (744050446), we obtain a palindrome (99999999).

The spelling of 644050447 in words is "six hundred forty-four million, fifty thousand, four hundred forty-seven".