129110921 has 2 divisors, whose sum is σ = 129110922. Its totient is φ = 129110920.

The previous prime is 129110893. The next prime is 129110941. The reversal of 129110921 is 129011921.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 78145600 + 50965321 = 8840^2 + 7139^2 .

It is an emirp because it is prime and its reverse (129011921) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129110921 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (129110941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64555460 + 64555461.

It is an arithmetic number, because the mean of its divisors is an integer number (64555461).

Almost surely, 2^129110921 is an apocalyptic number.

It is an amenable number.

129110921 is a deficient number, since it is larger than the sum of its proper divisors (1).

129110921 is an equidigital number, since it uses as much as digits as its factorization.

129110921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 324, while the sum is 26.

The square root of 129110921 is about 11362.6986671301. The cubic root of 129110921 is about 505.4222146234.

It can be divided in two parts, 129110 and 921, that added together give a palindrome (130031).

The spelling of 129110921 in words is "one hundred twenty-nine million, one hundred ten thousand, nine hundred twenty-one".