129128057 has 2 divisors, whose sum is σ = 129128058. Its totient is φ = 129128056.

The previous prime is 129127987. The next prime is 129128063. The reversal of 129128057 is 750821921.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 73342096 + 55785961 = 8564^2 + 7469^2 .

It is a cyclic number.

It is not a de Polignac number, because 129128057 - 2²⁶ = 62019193 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (122128057) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64564028 + 64564029.

It is an arithmetic number, because the mean of its divisors is an integer number (64564029).

Almost surely, 2^129128057 is an apocalyptic number.

It is an amenable number.

129128057 is a deficient number, since it is larger than the sum of its proper divisors (1).

129128057 is an equidigital number, since it uses as much as digits as its factorization.

129128057 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10080, while the sum is 35.

The square root of 129128057 is about 11363.4526883338. The cubic root of 129128057 is about 505.4445740330. Note that the first 3 decimals are identical.

Adding to 129128057 its reverse (750821921), we get a palindrome (879949978).

The spelling of 129128057 in words is "one hundred twenty-nine million, one hundred twenty-eight thousand, fifty-seven".