129539939 has 4 divisors (see below), whose sum is σ = 130485624. Its totient is φ = 128594256.

The previous prime is 129539903. The next prime is 129539941. The reversal of 129539939 is 939935921.

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 129539939 - 2¹² = 129535843 is a prime.

It is a super-2 number, since 2×129539939² = 33561191592247442, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129539989) 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, 472637 + ... + 472910.

It is an arithmetic number, because the mean of its divisors is an integer number (32621406).

Almost surely, 2^129539939 is an apocalyptic number.

129539939 is a deficient number, since it is larger than the sum of its proper divisors (945685).

129539939 is an equidigital number, since it uses as much as digits as its factorization.

129539939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 945684.

The product of its digits is 590490, while the sum is 50.

The square root of 129539939 is about 11381.5613603758. The cubic root of 129539939 is about 505.9814120873.

The spelling of 129539939 in words is "one hundred twenty-nine million, five hundred thirty-nine thousand, nine hundred thirty-nine".