43121212129 has 2 divisors, whose sum is σ = 43121212130. Its totient is φ = 43121212128.

The previous prime is 43121212093. The next prime is 43121212157. The reversal of 43121212129 is 92121212134.

It is an a-pointer prime, because the next prime (43121212157) can be obtained adding 43121212129 to its sum of digits (28).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 41844793600 + 1276418529 = 204560^2 + 35727^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43121212129 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 43121212097 and 43121212106.

It is not a weakly prime, because it can be changed into another prime (43121912129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21560606064 + 21560606065.

It is an arithmetic number, because the mean of its divisors is an integer number (21560606065).

Almost surely, 2^43121212129 is an apocalyptic number.

It is an amenable number.

43121212129 is a deficient number, since it is larger than the sum of its proper divisors (1).

43121212129 is an equidigital number, since it uses as much as digits as its factorization.

43121212129 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1728, while the sum is 28.

The spelling of 43121212129 in words is "forty-three billion, one hundred twenty-one million, two hundred twelve thousand, one hundred twenty-nine".