81216000061218 has 48 divisors (see below), whose sum is σ = 191993229245376. Its totient is φ = 24607301649120.

The previous prime is 81216000061199. The next prime is 81216000061303.

81216000061218 is a `hidden beast` number, since 8 + 1 + 21 + 6 + 0 + 0 + 0 + 0 + 612 + 18 = 666.

81216000061218 is nontrivially palindromic in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 28707805 + ... + 31409712.

It is an arithmetic number, because the mean of its divisors is an integer number (3999858942612).

Almost surely, 2^{81216000061218} is an apocalyptic number.

81216000061218 is an abundant number, since it is smaller than the sum of its proper divisors (110777229184158).

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

81216000061218 is a wasteful number, since it uses less digits than its factorization.

81216000061218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60124359 (or 60124356 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 36.

The spelling of 81216000061218 in words is "eighty-one trillion, two hundred sixteen billion, sixty-one thousand, two hundred eighteen".