66571152121 has 2 divisors, whose sum is σ = 66571152122. Its totient is φ = 66571152120.

The previous prime is 66571152119. The next prime is 66571152139. The reversal of 66571152121 is 12125117566.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 46360549225 + 20210602896 = 215315^2 + 142164^2 .

It is a cyclic number.

It is not a de Polignac number, because 66571152121 - 2¹ = 66571152119 is a prime.

Together with 66571152119, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (66571159121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33285576060 + 33285576061.

It is an arithmetic number, because the mean of its divisors is an integer number (33285576061).

Almost surely, 2^66571152121 is an apocalyptic number.

It is an amenable number.

66571152121 is a deficient number, since it is larger than the sum of its proper divisors (1).

66571152121 is an equidigital number, since it uses as much as digits as its factorization.

66571152121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 25200, while the sum is 37.

Adding to 66571152121 its reverse (12125117566), we get a palindrome (78696269687).

The spelling of 66571152121 in words is "sixty-six billion, five hundred seventy-one million, one hundred fifty-two thousand, one hundred twenty-one".