521525729 has 2 divisors, whose sum is σ = 521525730. Its totient is φ = 521525728.

The previous prime is 521525723. The next prime is 521525749. The reversal of 521525729 is 927525125.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 518017600 + 3508129 = 22760^2 + 1873^2 .

It is a cyclic number.

It is not a de Polignac number, because 521525729 - 2²⁸ = 253090273 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 521525692 and 521525701.

It is not a weakly prime, because it can be changed into another prime (521525723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260762864 + 260762865.

It is an arithmetic number, because the mean of its divisors is an integer number (260762865).

Almost surely, 2^521525729 is an apocalyptic number.

It is an amenable number.

521525729 is a deficient number, since it is larger than the sum of its proper divisors (1).

521525729 is an equidigital number, since it uses as much as digits as its factorization.

521525729 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 63000, while the sum is 38.

The square root of 521525729 is about 22836.9378201194. The cubic root of 521525729 is about 804.9308629846.

The spelling of 521525729 in words is "five hundred twenty-one million, five hundred twenty-five thousand, seven hundred twenty-nine".