129857844 has 48 divisors (see below), whose sum is σ = 310625280. Its totient is φ = 42207360.

The previous prime is 129857843. The next prime is 129857857. The reversal of 129857844 is 448758921.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 129857793 and 129857802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129857843) 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 15 ways as a sum of consecutive naturals, for example, 120942 + ... + 122010.

It is an arithmetic number, because the mean of its divisors is an integer number (6471360).

Almost surely, 2^129857844 is an apocalyptic number.

It is an amenable number.

129857844 is an abundant number, since it is smaller than the sum of its proper divisors (180767436).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

129857844 is a wasteful number, since it uses less digits than its factorization.

129857844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1320 (or 1318 counting only the distinct ones).

The product of its digits is 645120, while the sum is 48.

The square root of 129857844 is about 11395.5185928504. The cubic root of 129857844 is about 506.3949849636.

The spelling of 129857844 in words is "one hundred twenty-nine million, eight hundred fifty-seven thousand, eight hundred forty-four".