521124191993 has 2 divisors, whose sum is σ = 521124191994. Its totient is φ = 521124191992.

The previous prime is 521124191989. The next prime is 521124192053. The reversal of 521124191993 is 399191421125.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 415705141504 + 105419050489 = 644752^2 + 324683^2 .

It is a cyclic number.

It is not a de Polignac number, because 521124191993 - 2² = 521124191989 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (521124199993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260562095996 + 260562095997.

It is an arithmetic number, because the mean of its divisors is an integer number (260562095997).

Almost surely, 2^521124191993 is an apocalyptic number.

It is an amenable number.

521124191993 is a deficient number, since it is larger than the sum of its proper divisors (1).

521124191993 is an equidigital number, since it uses as much as digits as its factorization.

521124191993 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 174960, while the sum is 47.

The spelling of 521124191993 in words is "five hundred twenty-one billion, one hundred twenty-four million, one hundred ninety-one thousand, nine hundred ninety-three".