81841208118381 has 12 divisors (see below), whose sum is σ = 118243722759552. Its totient is φ = 54547584935496.

The previous prime is 81841208118379. The next prime is 81841208118421. The reversal of 81841208118381 is 18381180214818.

81841208118381 is a `hidden beast` number, since 8 + 1 + 8 + 41 + 208 + 1 + 18 + 381 = 666.

It is not a de Polignac number, because 81841208118381 - 2¹ = 81841208118379 is a prime.

It is a super-2 number, since 2×81841208118381² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81841208118361) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1101667191 + ... + 1101741476.

It is an arithmetic number, because the mean of its divisors is an integer number (9853643563296).

Almost surely, 2^{81841208118381} is an apocalyptic number.

It is an amenable number.

81841208118381 is a deficient number, since it is larger than the sum of its proper divisors (36402514641171).

81841208118381 is a wasteful number, since it uses less digits than its factorization.

81841208118381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2203412800 (or 2203412797 counting only the distinct ones).

The product of its (nonzero) digits is 786432, while the sum is 54.

The spelling of 81841208118381 in words is "eighty-one trillion, eight hundred forty-one billion, two hundred eight million, one hundred eighteen thousand, three hundred eighty-one".