81812124834208 has 24 divisors (see below), whose sum is σ = 170542186695972. Its totient is φ = 38499823451136.

The previous prime is 81812124834173. The next prime is 81812124834227. The reversal of 81812124834208 is 80243842121818.

It can be written as a sum of positive squares in 2 ways, for example, as 77428243646224 + 4383881187984 = 8799332^2 + 2093772^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 75194967135 + ... + 75194968222.

Almost surely, 2^{81812124834208} is an apocalyptic number.

It is an amenable number.

81812124834208 is an abundant number, since it is smaller than the sum of its proper divisors (88730061861764).

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

81812124834208 is a wasteful number, since it uses less digits than its factorization.

81812124834208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 150389935384 (or 150389935376 counting only the distinct ones).

The product of its (nonzero) digits is 1572864, while the sum is 52.

The spelling of 81812124834208 in words is "eighty-one trillion, eight hundred twelve billion, one hundred twenty-four million, eight hundred thirty-four thousand, two hundred eight".