811990129 has 2 divisors, whose sum is σ = 811990130. Its totient is φ = 811990128.

The previous prime is 811990019. The next prime is 811990141. The reversal of 811990129 is 921099118.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 803609104 + 8381025 = 28348^2 + 2895^2 .

It is a cyclic number.

It is not a de Polignac number, because 811990129 - 2⁹ = 811989617 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 811990091 and 811990100.

It is not a weakly prime, because it can be changed into another prime (811993129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 405995064 + 405995065.

It is an arithmetic number, because the mean of its divisors is an integer number (405995065).

Almost surely, 2^811990129 is an apocalyptic number.

It is an amenable number.

811990129 is a deficient number, since it is larger than the sum of its proper divisors (1).

811990129 is an equidigital number, since it uses as much as digits as its factorization.

811990129 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11664, while the sum is 40.

The square root of 811990129 is about 28495.4404949283. The cubic root of 811990129 is about 932.9325586996.

The spelling of 811990129 in words is "eight hundred eleven million, nine hundred ninety thousand, one hundred twenty-nine".