129423747 has 4 divisors (see below), whose sum is σ = 172565000. Its totient is φ = 86282496.

The previous prime is 129423733. The next prime is 129423751. The reversal of 129423747 is 747324921.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 129423747 - 2⁴ = 129423731 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129423727) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21570622 + ... + 21570627.

It is an arithmetic number, because the mean of its divisors is an integer number (43141250).

Almost surely, 2^129423747 is an apocalyptic number.

129423747 is a deficient number, since it is larger than the sum of its proper divisors (43141253).

129423747 is an equidigital number, since it uses as much as digits as its factorization.

129423747 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43141252.

The product of its digits is 84672, while the sum is 39.

The square root of 129423747 is about 11376.4558189271. The cubic root of 129423747 is about 505.8300853249.

The spelling of 129423747 in words is "one hundred twenty-nine million, four hundred twenty-three thousand, seven hundred forty-seven".