129189923 has 2 divisors, whose sum is σ = 129189924. Its totient is φ = 129189922.

The previous prime is 129189889. The next prime is 129189937. The reversal of 129189923 is 329981921.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 129189923 - 2⁶ = 129189859 is a prime.

It is not a weakly prime, because it can be changed into another prime (129189943) 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, 64594961 + 64594962.

It is an arithmetic number, because the mean of its divisors is an integer number (64594962).

Almost surely, 2^129189923 is an apocalyptic number.

129189923 is a deficient number, since it is larger than the sum of its proper divisors (1).

129189923 is an equidigital number, since it uses as much as digits as its factorization.

129189923 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 69984, while the sum is 44.

The square root of 129189923 is about 11366.1745103619. The cubic root of 129189923 is about 505.5252816196.

The spelling of 129189923 in words is "one hundred twenty-nine million, one hundred eighty-nine thousand, nine hundred twenty-three".