81341992988 has 6 divisors (see below), whose sum is σ = 142348487736. Its totient is φ = 40670996492.

The previous prime is 81341992987. The next prime is 81341993059. The reversal of 81341992988 is 88929914318.

It is a self number, because there is not a number n which added to its sum of digits gives 81341992988.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81341992981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10167749120 + ... + 10167749127.

It is an arithmetic number, because the mean of its divisors is an integer number (23724747956).

Almost surely, 2^81341992988 is an apocalyptic number.

It is an amenable number.

81341992988 is a deficient number, since it is larger than the sum of its proper divisors (61006494748).

81341992988 is a wasteful number, since it uses less digits than its factorization.

81341992988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20335498251 (or 20335498249 counting only the distinct ones).

The product of its digits is 8957952, while the sum is 62.

The spelling of 81341992988 in words is "eighty-one billion, three hundred forty-one million, nine hundred ninety-two thousand, nine hundred eighty-eight".