71981056 has 48 divisors (see below), whose sum is σ = 164520720. Its totient is φ = 30842880.

The previous prime is 71981047. The next prime is 71981057. The reversal of 71981056 is 65018917.

It is a Smith number, since the sum of its digits (37) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71981057) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11826 + ... + 16846.

It is an arithmetic number, because the mean of its divisors is an integer number (3427515).

Almost surely, 2^71981056 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 71981056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82260360).

71981056 is an abundant number, since it is smaller than the sum of its proper divisors (92539664).

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

71981056 is an equidigital number, since it uses as much as digits as its factorization.

71981056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5050 (or 5030 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 37.

The square root of 71981056 is about 8484.1650148969. The cubic root of 71981056 is about 415.9802751989.

The spelling of 71981056 in words is "seventy-one million, nine hundred eighty-one thousand, fifty-six".