513106123021 has 2 divisors, whose sum is σ = 513106123022. Its totient is φ = 513106123020.

The previous prime is 513106122953. The next prime is 513106123027. The reversal of 513106123021 is 120321601315.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 261132242121 + 251973880900 = 511011^2 + 501970^2 .

It is a cyclic number.

It is not a de Polignac number, because 513106123021 - 2⁹ = 513106122509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (513106123027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 256553061510 + 256553061511.

It is an arithmetic number, because the mean of its divisors is an integer number (256553061511).

Almost surely, 2^513106123021 is an apocalyptic number.

It is an amenable number.

513106123021 is a deficient number, since it is larger than the sum of its proper divisors (1).

513106123021 is an equidigital number, since it uses as much as digits as its factorization.

513106123021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1080, while the sum is 25.

Adding to 513106123021 its reverse (120321601315), we get a palindrome (633427724336).

The spelling of 513106123021 in words is "five hundred thirteen billion, one hundred six million, one hundred twenty-three thousand, twenty-one".