71661723616 has 192 divisors, whose sum is σ = 175436997120. Its totient is φ = 28130457600.

The previous prime is 71661723613. The next prime is 71661723641. The reversal of 71661723616 is 61632716617.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71661723613) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 18481870 + ... + 18485746.

It is an arithmetic number, because the mean of its divisors is an integer number (913734360).

Almost surely, 2^71661723616 is an apocalyptic number.

71661723616 is a gapful number since it is divisible by the number (76) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71661723616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (87718498560).

71661723616 is an abundant number, since it is smaller than the sum of its proper divisors (103775273504).

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

71661723616 is a wasteful number, since it uses less digits than its factorization.

71661723616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4057 (or 4049 counting only the distinct ones).

The product of its digits is 381024, while the sum is 46.

The spelling of 71661723616 in words is "seventy-one billion, six hundred sixty-one million, seven hundred twenty-three thousand, six hundred sixteen".