129189479 has 4 divisors (see below), whose sum is σ = 129466584. Its totient is φ = 128912376.

The previous prime is 129189457. The next prime is 129189481. The reversal of 129189479 is 974981921.

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

It is a cyclic number.

It is not a de Polignac number, because 129189479 - 2²⁴ = 112412263 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129189439) 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, 137852 + ... + 138785.

It is an arithmetic number, because the mean of its divisors is an integer number (32366646).

Almost surely, 2^129189479 is an apocalyptic number.

129189479 is a deficient number, since it is larger than the sum of its proper divisors (277105).

129189479 is an equidigital number, since it uses as much as digits as its factorization.

129189479 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 277104.

The product of its digits is 326592, while the sum is 50.

The square root of 129189479 is about 11366.1549787076. The cubic root of 129189479 is about 505.5247024890.

The spelling of 129189479 in words is "one hundred twenty-nine million, one hundred eighty-nine thousand, four hundred seventy-nine".