521728834129 has 2 divisors, whose sum is σ = 521728834130. Its totient is φ = 521728834128.

The previous prime is 521728834117. The next prime is 521728834141. The reversal of 521728834129 is 921438827125.

It is a balanced prime because it is at equal distance from previous prime (521728834117) and next prime (521728834141).

It can be written as a sum of positive squares in only one way, i.e., 286166153025 + 235562681104 = 534945^2 + 485348^2 .

It is a cyclic number.

It is not a de Polignac number, because 521728834129 - 2¹⁹ = 521728309841 is a prime.

It is not a weakly prime, because it can be changed into another prime (521728834199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260864417064 + 260864417065.

It is an arithmetic number, because the mean of its divisors is an integer number (260864417065).

Almost surely, 2^521728834129 is an apocalyptic number.

It is an amenable number.

521728834129 is a deficient number, since it is larger than the sum of its proper divisors (1).

521728834129 is an equidigital number, since it uses as much as digits as its factorization.

521728834129 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1935360, while the sum is 52.

The spelling of 521728834129 in words is "five hundred twenty-one billion, seven hundred twenty-eight million, eight hundred thirty-four thousand, one hundred twenty-nine".