12165020561 has 2 divisors, whose sum is σ = 12165020562. Its totient is φ = 12165020560.

The previous prime is 12165020519. The next prime is 12165020603. The reversal of 12165020561 is 16502056121.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (12165020519) and next prime (12165020603).

It can be written as a sum of positive squares in only one way, i.e., 8771259025 + 3393761536 = 93655^2 + 58256^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12165020561 is a prime.

It is not a weakly prime, because it can be changed into another prime (12165020261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6082510280 + 6082510281.

It is an arithmetic number, because the mean of its divisors is an integer number (6082510281).

Almost surely, 2^12165020561 is an apocalyptic number.

It is an amenable number.

12165020561 is a deficient number, since it is larger than the sum of its proper divisors (1).

12165020561 is an equidigital number, since it uses as much as digits as its factorization.

12165020561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3600, while the sum is 29.

Adding to 12165020561 its reverse (16502056121), we get a palindrome (28667076682).

The spelling of 12165020561 in words is "twelve billion, one hundred sixty-five million, twenty thousand, five hundred sixty-one".