129572161 has 2 divisors, whose sum is σ = 129572162. Its totient is φ = 129572160.

The previous prime is 129572159. The next prime is 129572173. The reversal of 129572161 is 161275921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 128482225 + 1089936 = 11335^2 + 1044^2 .

It is a cyclic number.

It is not a de Polignac number, because 129572161 - 2¹ = 129572159 is a prime.

Together with 129572159, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (129578161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64786080 + 64786081.

It is an arithmetic number, because the mean of its divisors is an integer number (64786081).

Almost surely, 2^129572161 is an apocalyptic number.

It is an amenable number.

129572161 is a deficient number, since it is larger than the sum of its proper divisors (1).

129572161 is an equidigital number, since it uses as much as digits as its factorization.

129572161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7560, while the sum is 34.

The square root of 129572161 is about 11382.9768074964. The cubic root of 129572161 is about 506.0233615215.

The spelling of 129572161 in words is "one hundred twenty-nine million, five hundred seventy-two thousand, one hundred sixty-one".