81066347387 has 2 divisors, whose sum is σ = 81066347388. Its totient is φ = 81066347386.

The previous prime is 81066347317. The next prime is 81066347429. The reversal of 81066347387 is 78374366018.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81066347387 - 2²⁴ = 81049570171 is a prime.

It is not a weakly prime, because it can be changed into another prime (81066347317) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40533173693 + 40533173694.

It is an arithmetic number, because the mean of its divisors is an integer number (40533173694).

Almost surely, 2^81066347387 is an apocalyptic number.

81066347387 is a deficient number, since it is larger than the sum of its proper divisors (1).

81066347387 is an equidigital number, since it uses as much as digits as its factorization.

81066347387 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4064256, while the sum is 53.

The spelling of 81066347387 in words is "eighty-one billion, sixty-six million, three hundred forty-seven thousand, three hundred eighty-seven".