12121204657 has 2 divisors, whose sum is σ = 12121204658. Its totient is φ = 12121204656.

The previous prime is 12121204639. The next prime is 12121204661. The reversal of 12121204657 is 75640212121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9507030016 + 2614174641 = 97504^2 + 51129^2 .

It is an emirp because it is prime and its reverse (75640212121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12121204657 - 2¹¹ = 12121202609 is a prime.

It is not a weakly prime, because it can be changed into another prime (12121204057) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6060602328 + 6060602329.

It is an arithmetic number, because the mean of its divisors is an integer number (6060602329).

Almost surely, 2^12121204657 is an apocalyptic number.

It is an amenable number.

12121204657 is a deficient number, since it is larger than the sum of its proper divisors (1).

12121204657 is an equidigital number, since it uses as much as digits as its factorization.

12121204657 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6720, while the sum is 31.

Adding to 12121204657 its reverse (75640212121), we get a palindrome (87761416778).

The spelling of 12121204657 in words is "twelve billion, one hundred twenty-one million, two hundred four thousand, six hundred fifty-seven".