129942739 has 4 divisors (see below), whose sum is σ = 129970656. Its totient is φ = 129914824.

The previous prime is 129942737. The next prime is 129942763. The reversal of 129942739 is 937249921.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 937249921 = 1279 ⋅732799.

It is a cyclic number.

It is not a de Polignac number, because 129942739 - 2¹ = 129942737 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129942737) 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 3 ways as a sum of consecutive naturals, for example, 5104 + ... + 16909.

It is an arithmetic number, because the mean of its divisors is an integer number (32492664).

Almost surely, 2^129942739 is an apocalyptic number.

129942739 is a deficient number, since it is larger than the sum of its proper divisors (27917).

129942739 is an equidigital number, since it uses as much as digits as its factorization.

129942739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27916.

The product of its digits is 244944, while the sum is 46.

The square root of 129942739 is about 11399.2429134570. The cubic root of 129942739 is about 506.5053133965.

The spelling of 129942739 in words is "one hundred twenty-nine million, nine hundred forty-two thousand, seven hundred thirty-nine".