71644644618 has 32 divisors (see below), whose sum is σ = 148810016256. Its totient is φ = 22978006128.

The previous prime is 71644644613. The next prime is 71644644641. The reversal of 71644644618 is 81644644617.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (71644644613) 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, 2055046 + ... + 2089617.

It is an arithmetic number, because the mean of its divisors is an integer number (4650313008).

Almost surely, 2^71644644618 is an apocalyptic number.

71644644618 is an abundant number, since it is smaller than the sum of its proper divisors (77165371638).

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

71644644618 is a wasteful number, since it uses less digits than its factorization.

71644644618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4144778.

The product of its digits is 3096576, while the sum is 51.

Subtracting 71644644618 from its reverse (81644644617), we obtain a palindrome (9999999999).

The spelling of 71644644618 in words is "seventy-one billion, six hundred forty-four million, six hundred forty-four thousand, six hundred eighteen".