81133617884 has 24 divisors (see below), whose sum is σ = 156395261568. Its totient is φ = 36520867440.

The previous prime is 81133617863. The next prime is 81133617931. The reversal of 81133617884 is 48871633118.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8946662 + ... + 8955725.

It is an arithmetic number, because the mean of its divisors is an integer number (6516469232).

Almost surely, 2^81133617884 is an apocalyptic number.

It is an amenable number.

81133617884 is a deficient number, since it is larger than the sum of its proper divisors (75261643684).

81133617884 is a wasteful number, since it uses less digits than its factorization.

81133617884 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17902505 (or 17902503 counting only the distinct ones).

The product of its digits is 774144, while the sum is 50.

The spelling of 81133617884 in words is "eighty-one billion, one hundred thirty-three million, six hundred seventeen thousand, eight hundred eighty-four".