81707316982129 has 2 divisors, whose sum is σ = 81707316982130. Its totient is φ = 81707316982128.

The previous prime is 81707316982103. The next prime is 81707316982177. The reversal of 81707316982129 is 92128961370718.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 77817539030625 + 3889777951504 = 8821425^2 + 1972252^2 .

It is a cyclic number.

It is not a de Polignac number, because 81707316982129 - 2⁷ = 81707316982001 is a prime.

It is a super-2 number, since 2×81707316982129² (a number of 29 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (81707316982199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40853658491064 + 40853658491065.

It is an arithmetic number, because the mean of its divisors is an integer number (40853658491065).

Almost surely, 2^{81707316982129} is an apocalyptic number.

It is an amenable number.

81707316982129 is a deficient number, since it is larger than the sum of its proper divisors (1).

81707316982129 is an equidigital number, since it uses as much as digits as its factorization.

81707316982129 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18289152, while the sum is 64.

The spelling of 81707316982129 in words is "eighty-one trillion, seven hundred seven billion, three hundred sixteen million, nine hundred eighty-two thousand, one hundred twenty-nine".