81268816616 has 32 divisors (see below), whose sum is σ = 164823452640. Its totient is φ = 37343437248.

The previous prime is 81268816609. The next prime is 81268816621. The reversal of 81268816616 is 61661886218.

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, 1697606 + ... + 1744821.

It is an arithmetic number, because the mean of its divisors is an integer number (5150732895).

Almost surely, 2^81268816616 is an apocalyptic number.

It is an amenable number.

81268816616 is an abundant number, since it is smaller than the sum of its proper divisors (83554636024).

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

81268816616 is a wasteful number, since it uses less digits than its factorization.

81268816616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3442673 (or 3442669 counting only the distinct ones).

The product of its digits is 1327104, while the sum is 53.

The spelling of 81268816616 in words is "eighty-one billion, two hundred sixty-eight million, eight hundred sixteen thousand, six hundred sixteen".