65657112211121 has 2 divisors, whose sum is σ = 65657112211122. Its totient is φ = 65657112211120.

The previous prime is 65657112211099. The next prime is 65657112211129. The reversal of 65657112211121 is 12111221175656.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 64966243706896 + 690868504225 = 8060164^2 + 831185^2 .

It is a cyclic number.

It is not a de Polignac number, because 65657112211121 - 2³⁰ = 65656038469297 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 (65657112211129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32828556105560 + 32828556105561.

It is an arithmetic number, because the mean of its divisors is an integer number (32828556105561).

Almost surely, 2^{65657112211121} is an apocalyptic number.

It is an amenable number.

65657112211121 is a deficient number, since it is larger than the sum of its proper divisors (1).

65657112211121 is an equidigital number, since it uses as much as digits as its factorization.

65657112211121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 50400, while the sum is 41.

Adding to 65657112211121 its reverse (12111221175656), we get a palindrome (77768333386777).

The spelling of 65657112211121 in words is "sixty-five trillion, six hundred fifty-seven billion, one hundred twelve million, two hundred eleven thousand, one hundred twenty-one".