81990181082 has 16 divisors (see below), whose sum is σ = 124857932352. Its totient is φ = 40371233760.

The previous prime is 81990181073. The next prime is 81990181171. The reversal of 81990181082 is 28018109918.

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, 370907 + ... + 549137.

It is an arithmetic number, because the mean of its divisors is an integer number (7803620772).

Almost surely, 2^81990181082 is an apocalyptic number.

81990181082 is a deficient number, since it is larger than the sum of its proper divisors (42867751270).

81990181082 is a wasteful number, since it uses less digits than its factorization.

81990181082 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 181733.

The product of its (nonzero) digits is 82944, while the sum is 47.

The spelling of 81990181082 in words is "eighty-one billion, nine hundred ninety million, one hundred eighty-one thousand, eighty-two".