513065821 has 2 divisors, whose sum is σ = 513065822. Its totient is φ = 513065820.

The previous prime is 513065747. The next prime is 513065843. The reversal of 513065821 is 128560315.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 490844025 + 22221796 = 22155^2 + 4714^2 .

It is a cyclic number.

It is not a de Polignac number, because 513065821 - 2⁹ = 513065309 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (513065851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 256532910 + 256532911.

It is an arithmetic number, because the mean of its divisors is an integer number (256532911).

Almost surely, 2^513065821 is an apocalyptic number.

It is an amenable number.

513065821 is a deficient number, since it is larger than the sum of its proper divisors (1).

513065821 is an equidigital number, since it uses as much as digits as its factorization.

513065821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7200, while the sum is 31.

The square root of 513065821 is about 22650.9562932782. The cubic root of 513065821 is about 800.5547303580.

The spelling of 513065821 in words is "five hundred thirteen million, sixty-five thousand, eight hundred twenty-one".