12568536951661 has 2 divisors, whose sum is σ = 12568536951662. Its totient is φ = 12568536951660.

The previous prime is 12568536951643. The next prime is 12568536951823. The reversal of 12568536951661 is 16615963586521.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7259171661225 + 5309365290436 = 2694285^2 + 2304206^2 .

It is a cyclic number.

It is not a de Polignac number, because 12568536951661 - 2¹⁹ = 12568536427373 is a prime.

It is a super-2 number, since 2×12568536951661² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 12568536951593 and 12568536951602.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12568536952661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6284268475830 + 6284268475831.

It is an arithmetic number, because the mean of its divisors is an integer number (6284268475831).

Almost surely, 2^{12568536951661} is an apocalyptic number.

It is an amenable number.

12568536951661 is a deficient number, since it is larger than the sum of its proper divisors (1).

12568536951661 is an equidigital number, since it uses as much as digits as its factorization.

12568536951661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 69984000, while the sum is 64.

The spelling of 12568536951661 in words is "twelve trillion, five hundred sixty-eight billion, five hundred thirty-six million, nine hundred fifty-one thousand, six hundred sixty-one".