129494921 has 2 divisors, whose sum is σ = 129494922. Its totient is φ = 129494920.

The previous prime is 129494881. The next prime is 129494923.

129494921 is nontrivially palindromic in base 10.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 128504896 + 990025 = 11336^2 + 995^2 .

It is a palprime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129494921 is a prime.

Together with 129494923, it forms a pair of twin primes.

It is a Chen prime.

It is an alternating number because its digits alternate between odd and even.

It is not a weakly prime, because it can be changed into another prime (129494923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64747460 + 64747461.

It is an arithmetic number, because the mean of its divisors is an integer number (64747461).

Almost surely, 2^129494921 is an apocalyptic number.

It is an amenable number.

129494921 is a deficient number, since it is larger than the sum of its proper divisors (1).

129494921 is an equidigital number, since it uses as much as digits as its factorization.

129494921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46656, while the sum is 41.

The square root of 129494921 is about 11379.5835161046. The cubic root of 129494921 is about 505.9227920443.

The spelling of 129494921 in words is "one hundred twenty-nine million, four hundred ninety-four thousand, nine hundred twenty-one".