129257897 has 2 divisors, whose sum is σ = 129257898. Its totient is φ = 129257896.

The previous prime is 129257873. The next prime is 129257899. The reversal of 129257897 is 798752921.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 125978176 + 3279721 = 11224^2 + 1811^2 .

It is a cyclic number.

It is not a de Polignac number, because 129257897 - 2²² = 125063593 is a prime.

Together with 129257899, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (129257899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64628948 + 64628949.

It is an arithmetic number, because the mean of its divisors is an integer number (64628949).

Almost surely, 2^129257897 is an apocalyptic number.

It is an amenable number.

129257897 is a deficient number, since it is larger than the sum of its proper divisors (1).

129257897 is an equidigital number, since it uses as much as digits as its factorization.

129257897 is an evil number, because the sum of its binary digits is even.

The product of its digits is 635040, while the sum is 50.

The square root of 129257897 is about 11369.1643052601. The cubic root of 129257897 is about 505.6139277249.

The spelling of 129257897 in words is "one hundred twenty-nine million, two hundred fifty-seven thousand, eight hundred ninety-seven".