129040243 has 4 divisors (see below), whose sum is σ = 132187608. Its totient is φ = 125892880.

The previous prime is 129040231. The next prime is 129040253. The reversal of 129040243 is 342040921.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129040243 is a prime.

It is not an unprimeable number, because it can be changed into a prime (129040253) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1573621 + ... + 1573702.

It is an arithmetic number, because the mean of its divisors is an integer number (33046902).

Almost surely, 2^129040243 is an apocalyptic number.

129040243 is a deficient number, since it is larger than the sum of its proper divisors (3147365).

129040243 is an equidigital number, since it uses as much as digits as its factorization.

129040243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3147364.

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 129040243 is about 11359.5881527457. The cubic root of 129040243 is about 505.3299715832.

The spelling of 129040243 in words is "one hundred twenty-nine million, forty thousand, two hundred forty-three".