129189457 has 2 divisors, whose sum is σ = 129189458. Its totient is φ = 129189456.

The previous prime is 129189439. The next prime is 129189481. The reversal of 129189457 is 754981921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 92756161 + 36433296 = 9631^2 + 6036^2 .

It is a cyclic number.

It is not a de Polignac number, because 129189457 - 2¹⁵ = 129156689 is a prime.

It is not a weakly prime, because it can be changed into another prime (129189857) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64594728 + 64594729.

It is an arithmetic number, because the mean of its divisors is an integer number (64594729).

Almost surely, 2^129189457 is an apocalyptic number.

It is an amenable number.

129189457 is a deficient number, since it is larger than the sum of its proper divisors (1).

129189457 is an equidigital number, since it uses as much as digits as its factorization.

129189457 is an evil number, because the sum of its binary digits is even.

The product of its digits is 181440, while the sum is 46.

The square root of 129189457 is about 11366.1540109221. The cubic root of 129189457 is about 505.5246737933.

The spelling of 129189457 in words is "one hundred twenty-nine million, one hundred eighty-nine thousand, four hundred fifty-seven".