12129831 has 28 divisors (see below), whose sum is σ = 20793232. Its totient is φ = 6928416.

The previous prime is 12129829. The next prime is 12129851. The reversal of 12129831 is 13892121.

12129831 is digitally balanced in base 2 and base 8, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 12129831 - 2¹ = 12129829 is a prime.

It is a super-2 number, since 2×12129831² = 294265600177122, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

12129831 is strictly pandigital in base 8.

It is a junction number, because it is equal to n+sod(n) for n = 12129795 and 12129804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12129811) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 3915 + ... + 6291.

Almost surely, 2^12129831 is an apocalyptic number.

12129831 is a deficient number, since it is larger than the sum of its proper divisors (8663401).

12129831 is an frugal number, since it uses more digits than its factorization.

12129831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2402 (or 2387 counting only the distinct ones).

The product of its digits is 864, while the sum is 27.

The square root of 12129831 is about 3482.7906913853. The cubic root of 12129831 is about 229.7655518992.

The spelling of 12129831 in words is "twelve million, one hundred twenty-nine thousand, eight hundred thirty-one".