81181612627 has 2 divisors, whose sum is σ = 81181612628. Its totient is φ = 81181612626.

The previous prime is 81181612621. The next prime is 81181612679. The reversal of 81181612627 is 72621618118.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81181612627 - 2¹¹ = 81181610579 is a prime.

It is a super-2 number, since 2×81181612627² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (81181612621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40590806313 + 40590806314.

It is an arithmetic number, because the mean of its divisors is an integer number (40590806314).

Almost surely, 2^81181612627 is an apocalyptic number.

81181612627 is a deficient number, since it is larger than the sum of its proper divisors (1).

81181612627 is an equidigital number, since it uses as much as digits as its factorization.

81181612627 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 64512, while the sum is 43.

The spelling of 81181612627 in words is "eighty-one billion, one hundred eighty-one million, six hundred twelve thousand, six hundred twenty-seven".