820006129 has 2 divisors, whose sum is σ = 820006130. Its totient is φ = 820006128.

The previous prime is 820006111. The next prime is 820006151. The reversal of 820006129 is 921600028.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 715455504 + 104550625 = 26748^2 + 10225^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-820006129 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 820006097 and 820006106.

It is not a weakly prime, because it can be changed into another prime (820007129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410003064 + 410003065.

It is an arithmetic number, because the mean of its divisors is an integer number (410003065).

Almost surely, 2^820006129 is an apocalyptic number.

It is an amenable number.

820006129 is a deficient number, since it is larger than the sum of its proper divisors (1).

820006129 is an equidigital number, since it uses as much as digits as its factorization.

820006129 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 820006129 is about 28635.7491433348. The cubic root of 820006129 is about 935.9924942936.

The spelling of 820006129 in words is "eight hundred twenty million, six thousand, one hundred twenty-nine".