71561763840 has 1056 divisors, whose sum is σ = 289580083200. Its totient is φ = 15067250688.

The previous prime is 71561763829. The next prime is 71561763853. The reversal of 71561763840 is 4836716517.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 71561763840.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1522590697 + ... + 1522590743.

Almost surely, 2^71561763840 is an apocalyptic number.

71561763840 is a gapful number since it is divisible by the number (70) 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 71561763840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (144790041600).

71561763840 is an abundant number, since it is smaller than the sum of its proper divisors (218018319360).

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

71561763840 is a wasteful number, since it uses less digits than its factorization.

71561763840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130 (or 81 counting only the distinct ones).

The product of its (nonzero) digits is 846720, while the sum is 48.

The spelling of 71561763840 in words is "seventy-one billion, five hundred sixty-one million, seven hundred sixty-three thousand, eight hundred forty".