129346921 has 16 divisors (see below), whose sum is σ = 143320320. Its totient is φ = 115758720.

The previous prime is 129346909. The next prime is 129346969. The reversal of 129346921 is 129643921.

It is not a de Polignac number, because 129346921 - 2⁷ = 129346793 is a prime.

It is not an unprimeable number, because it can be changed into a prime (129346981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 279136 + ... + 279598.

It is an arithmetic number, because the mean of its divisors is an integer number (8957520).

Almost surely, 2^129346921 is an apocalyptic number.

129346921 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

129346921 is a deficient number, since it is larger than the sum of its proper divisors (13973399).

129346921 is a wasteful number, since it uses less digits than its factorization.

129346921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 816.

The product of its digits is 23328, while the sum is 37.

The square root of 129346921 is about 11373.0787828099. The cubic root of 129346921 is about 505.7299785185.

The spelling of 129346921 in words is "one hundred twenty-nine million, three hundred forty-six thousand, nine hundred twenty-one".