521722124263397 has 2 divisors, whose sum is σ = 521722124263398. Its totient is φ = 521722124263396.

The previous prime is 521722124263369. The next prime is 521722124263447. The reversal of 521722124263397 is 793362421227125.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 520411479375841 + 1310644887556 = 22812529^2 + 1144834^2 .

It is a cyclic number.

It is not a de Polignac number, because 521722124263397 - 2¹⁰ = 521722124262373 is a prime.

It is a super-2 number, since 2×521722124263397² (a number of 30 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (521722124263357) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260861062131698 + 260861062131699.

It is an arithmetic number, because the mean of its divisors is an integer number (260861062131699).

Almost surely, 2^{521722124263397} is an apocalyptic number.

It is an amenable number.

521722124263397 is a deficient number, since it is larger than the sum of its proper divisors (1).

521722124263397 is an equidigital number, since it uses as much as digits as its factorization.

521722124263397 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15240960, while the sum is 56.

The spelling of 521722124263397 in words is "five hundred twenty-one trillion, seven hundred twenty-two billion, one hundred twenty-four million, two hundred sixty-three thousand, three hundred ninety-seven".