81589839756 has 24 divisors (see below), whose sum is σ = 191588885040. Its totient is φ = 27023385792.

The previous prime is 81589839743. The next prime is 81589839787. The reversal of 81589839756 is 65793898518.

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, 21651471 + ... + 21655238.

It is an arithmetic number, because the mean of its divisors is an integer number (7982870210).

Almost surely, 2^81589839756 is an apocalyptic number.

It is an amenable number.

81589839756 is an abundant number, since it is smaller than the sum of its proper divisors (109999045284).

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

81589839756 is a wasteful number, since it uses less digits than its factorization.

81589839756 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43306873 (or 43306871 counting only the distinct ones).

The product of its digits is 130636800, while the sum is 69.

The spelling of 81589839756 in words is "eighty-one billion, five hundred eighty-nine million, eight hundred thirty-nine thousand, seven hundred fifty-six".