129275989 has 2 divisors, whose sum is σ = 129275990. Its totient is φ = 129275988.

The previous prime is 129275987. The next prime is 129276001. The reversal of 129275989 is 989572921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 103367889 + 25908100 = 10167^2 + 5090^2 .

It is a cyclic number.

It is not a de Polignac number, because 129275989 - 2¹ = 129275987 is a prime.

Together with 129275987, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (129275987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64637994 + 64637995.

It is an arithmetic number, because the mean of its divisors is an integer number (64637995).

Almost surely, 2^129275989 is an apocalyptic number.

It is an amenable number.

129275989 is a deficient number, since it is larger than the sum of its proper divisors (1).

129275989 is an equidigital number, since it uses as much as digits as its factorization.

129275989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 816480, while the sum is 52.

The square root of 129275989 is about 11369.9599383639. The cubic root of 129275989 is about 505.6375165878.

The spelling of 129275989 in words is "one hundred twenty-nine million, two hundred seventy-five thousand, nine hundred eighty-nine".