81481708712 has 32 divisors (see below), whose sum is σ = 153064080000. Its totient is φ = 40664697408.

The previous prime is 81481708687. The next prime is 81481708723. The reversal of 81481708712 is 21780718418.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11458214 + ... + 11465322.

It is an arithmetic number, because the mean of its divisors is an integer number (4783252500).

Almost surely, 2^81481708712 is an apocalyptic number.

It is an amenable number.

81481708712 is a deficient number, since it is larger than the sum of its proper divisors (71582371288).

81481708712 is a wasteful number, since it uses less digits than its factorization.

81481708712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9593 (or 9589 counting only the distinct ones).

The product of its (nonzero) digits is 200704, while the sum is 47.

The spelling of 81481708712 in words is "eighty-one billion, four hundred eighty-one million, seven hundred eight thousand, seven hundred twelve".