71247771644 has 72 divisors (see below), whose sum is σ = 145831371840. Its totient is φ = 30368628864.

The previous prime is 71247771601. The next prime is 71247771653. The reversal of 71247771644 is 44617774217.

It is a junction number, because it is equal to n+sod(n) for n = 71247771592 and 71247771601.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 45007277 + ... + 45008859.

It is an arithmetic number, because the mean of its divisors is an integer number (2025435720).

Almost surely, 2^71247771644 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71247771644, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72915685920).

71247771644 is an abundant number, since it is smaller than the sum of its proper divisors (74583600196).

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

71247771644 is a wasteful number, since it uses less digits than its factorization.

71247771644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2707 (or 2698 counting only the distinct ones).

The product of its digits is 1843968, while the sum is 50.

The spelling of 71247771644 in words is "seventy-one billion, two hundred forty-seven million, seven hundred seventy-one thousand, six hundred forty-four".