81171827132 has 48 divisors (see below), whose sum is σ = 163497868800. Its totient is φ = 34873493760.

The previous prime is 81171827131. The next prime is 81171827153. The reversal of 81171827132 is 23172817118.

It is a self number, because there is not a number n which added to its sum of digits gives 81171827132.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81171827131) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 249869 + ... + 474107.

It is an arithmetic number, because the mean of its divisors is an integer number (3406205600).

Almost surely, 2^81171827132 is an apocalyptic number.

It is an amenable number.

81171827132 is an abundant number, since it is smaller than the sum of its proper divisors (82326041668).

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

81171827132 is a wasteful number, since it uses less digits than its factorization.

81171827132 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 224706 (or 224704 counting only the distinct ones).

The product of its digits is 37632, while the sum is 41.

The spelling of 81171827132 in words is "eighty-one billion, one hundred seventy-one million, eight hundred twenty-seven thousand, one hundred thirty-two".