71811479520 has 576 divisors, whose sum is σ = 280215936000. Its totient is φ = 16577003520.

The previous prime is 71811479479. The next prime is 71811479521. The reversal of 71811479520 is 2597411817.

It is a happy number.

71811479520 is a `hidden beast` number, since 7 + 1 + 8 + 114 + 7 + 9 + 520 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71811479521) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 159936256 + ... + 159936704.

It is an arithmetic number, because the mean of its divisors is an integer number (486486000).

Almost surely, 2^71811479520 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 71811479520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (140107968000).

71811479520 is an abundant number, since it is smaller than the sum of its proper divisors (208404456480).

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

71811479520 is a wasteful number, since it uses less digits than its factorization.

71811479520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 943 (or 932 counting only the distinct ones).

The product of its (nonzero) digits is 141120, while the sum is 45.

The spelling of 71811479520 in words is "seventy-one billion, eight hundred eleven million, four hundred seventy-nine thousand, five hundred twenty".