81292488812 has 6 divisors (see below), whose sum is σ = 142261855428. Its totient is φ = 40646244404.

The previous prime is 81292488791. The next prime is 81292488877. The reversal of 81292488812 is 21888429218.

It is a happy 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 as a sum of consecutive naturals, namely, 10161561098 + ... + 10161561105.

It is an arithmetic number, because the mean of its divisors is an integer number (23710309238).

Almost surely, 2^81292488812 is an apocalyptic number.

It is an amenable number.

81292488812 is a deficient number, since it is larger than the sum of its proper divisors (60969366616).

81292488812 is a wasteful number, since it uses less digits than its factorization.

81292488812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20323122207 (or 20323122205 counting only the distinct ones).

The product of its digits is 1179648, while the sum is 53.

The spelling of 81292488812 in words is "eighty-one billion, two hundred ninety-two million, four hundred eighty-eight thousand, eight hundred twelve".