71644644616 has 32 divisors (see below), whose sum is σ = 135195661440. Its totient is φ = 35592652288.

The previous prime is 71644644613. The next prime is 71644644641. The reversal of 71644644616 is 61644644617.

It is a self number, because there is not a number n which added to its sum of digits gives 71644644616.

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 7 ways as a sum of consecutive naturals, for example, 3539661 + ... + 3559843.

It is an arithmetic number, because the mean of its divisors is an integer number (4224864420).

Almost surely, 2^71644644616 is an apocalyptic number.

It is an amenable number.

71644644616 is a deficient number, since it is larger than the sum of its proper divisors (63551016824).

71644644616 is a wasteful number, since it uses less digits than its factorization.

71644644616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23013 (or 23009 counting only the distinct ones).

The product of its digits is 2322432, while the sum is 49.

Subtracting from 71644644616 its reverse (61644644617), we obtain a palindrome (9999999999).

The spelling of 71644644616 in words is "seventy-one billion, six hundred forty-four million, six hundred forty-four thousand, six hundred sixteen".