81186767087108 has 6 divisors (see below), whose sum is σ = 142076842402446. Its totient is φ = 40593383543552.

The previous prime is 81186767087051. The next prime is 81186767087117. The reversal of 81186767087108 is 80178076768118.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 59307742127104 + 21879024960004 = 7701152^2 + 4677502^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10148345885885 + ... + 10148345885892.

It is an arithmetic number, because the mean of its divisors is an integer number (23679473733741).

Almost surely, 2^{81186767087108} is an apocalyptic number.

It is an amenable number.

81186767087108 is a deficient number, since it is larger than the sum of its proper divisors (60890075315338).

81186767087108 is a wasteful number, since it uses less digits than its factorization.

81186767087108 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20296691771781 (or 20296691771779 counting only the distinct ones).

The product of its (nonzero) digits is 50577408, while the sum is 68.

The spelling of 81186767087108 in words is "eighty-one trillion, one hundred eighty-six billion, seven hundred sixty-seven million, eighty-seven thousand, one hundred eight".