81868632100 has 36 divisors (see below), whose sum is σ = 178008231744. Its totient is φ = 32682328480.

The previous prime is 81868632077. The next prime is 81868632151. The reversal of 81868632100 is 123686818.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 763504 + ... + 864103.

It is an arithmetic number, because the mean of its divisors is an integer number (4944673104).

Almost surely, 2^81868632100 is an apocalyptic number.

It is an amenable number.

81868632100 is an abundant number, since it is smaller than the sum of its proper divisors (96139599644).

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

81868632100 is a wasteful number, since it uses less digits than its factorization.

81868632100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1628124 (or 1628117 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 43.

The spelling of 81868632100 in words is "eighty-one billion, eight hundred sixty-eight million, six hundred thirty-two thousand, one hundred".