129539819 has 4 divisors (see below), whose sum is σ = 129772944. Its totient is φ = 129306696.

The previous prime is 129539807. The next prime is 129539827. The reversal of 129539819 is 918935921.

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 129539819 - 2⁴ = 129539803 is a prime.

It is a super-2 number, since 2×129539819² = 33561129413105522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129539899) 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, 115727 + ... + 116840.

It is an arithmetic number, because the mean of its divisors is an integer number (32443236).

Almost surely, 2^129539819 is an apocalyptic number.

129539819 is a deficient number, since it is larger than the sum of its proper divisors (233125).

129539819 is an equidigital number, since it uses as much as digits as its factorization.

129539819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233124.

The product of its digits is 174960, while the sum is 47.

The square root of 129539819 is about 11381.5560886902. The cubic root of 129539819 is about 505.9812558477.

It can be divided in two parts, 1295 and 39819, that added together give a palindrome (41114).

The spelling of 129539819 in words is "one hundred twenty-nine million, five hundred thirty-nine thousand, eight hundred nineteen".