129961829 has 2 divisors, whose sum is σ = 129961830. Its totient is φ = 129961828.

The previous prime is 129961817. The next prime is 129961831. The reversal of 129961829 is 928169921.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 119399329 + 10562500 = 10927^2 + 3250^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129961829 is a prime.

Together with 129961831, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (129961849) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64980914 + 64980915.

It is an arithmetic number, because the mean of its divisors is an integer number (64980915).

Almost surely, 2^129961829 is an apocalyptic number.

It is an amenable number.

129961829 is a deficient number, since it is larger than the sum of its proper divisors (1).

129961829 is an equidigital number, since it uses as much as digits as its factorization.

129961829 is an evil number, because the sum of its binary digits is even.

The product of its digits is 139968, while the sum is 47.

The square root of 129961829 is about 11400.0802190160. The cubic root of 129961829 is about 506.5301158930.

The spelling of 129961829 in words is "one hundred twenty-nine million, nine hundred sixty-one thousand, eight hundred twenty-nine".