129840831 has 12 divisors (see below), whose sum is σ = 191087208. Its totient is φ = 84927024.

The previous prime is 129840829. The next prime is 129840833. The reversal of 129840831 is 138048921.

It is an interprime number because it is at equal distance from previous prime (129840829) and next prime (129840833).

It is not a de Polignac number, because 129840831 - 2¹ = 129840829 is a prime.

It is a super-2 number, since 2×129840831² = 33717282789541122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129840833) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 135625 + ... + 136578.

It is an arithmetic number, because the mean of its divisors is an integer number (15923934).

Almost surely, 2^129840831 is an apocalyptic number.

129840831 is a deficient number, since it is larger than the sum of its proper divisors (61246377).

129840831 is a wasteful number, since it uses less digits than its factorization.

129840831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 272262 (or 272259 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 129840831 is about 11394.7720907441. The cubic root of 129840831 is about 506.3728693078.

The spelling of 129840831 in words is "one hundred twenty-nine million, eight hundred forty thousand, eight hundred thirty-one".