641644446147 has 4 divisors (see below), whose sum is σ = 855525928200. Its totient is φ = 427762964096.

The previous prime is 641644446143. The next prime is 641644446187. The reversal of 641644446147 is 741644446146.

641644446147 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 641644446147 - 2² = 641644446143 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 641644446147.

It is not an unprimeable number, because it can be changed into a prime (641644446143) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 106940741022 + ... + 106940741027.

It is an arithmetic number, because the mean of its divisors is an integer number (213881482050).

Almost surely, 2^641644446147 is an apocalyptic number.

641644446147 is a deficient number, since it is larger than the sum of its proper divisors (213881482053).

641644446147 is a wasteful number, since it uses less digits than its factorization.

641644446147 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 213881482052.

The product of its digits is 6193152, while the sum is 51.

Subtracting 641644446147 from its reverse (741644446146), we obtain a palindrome (99999999999).

The spelling of 641644446147 in words is "six hundred forty-one billion, six hundred forty-four million, four hundred forty-six thousand, one hundred forty-seven".