12128839261 has 24 divisors (see below), whose sum is σ = 16132495680. Its totient is φ = 8895089280.

The previous prime is 12128839241. The next prime is 12128839267. The reversal of 12128839261 is 16293882121.

It is not a de Polignac number, because 12128839261 - 2⁹ = 12128838749 is a prime.

It is a super-2 number, since 2×12128839261² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12128839267) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 406771 + ... + 435568.

It is an arithmetic number, because the mean of its divisors is an integer number (672187320).

Almost surely, 2^12128839261 is an apocalyptic number.

12128839261 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12128839261 is a deficient number, since it is larger than the sum of its proper divisors (4003656419).

12128839261 is a wasteful number, since it uses less digits than its factorization.

12128839261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 842385 (or 842374 counting only the distinct ones).

The product of its digits is 82944, while the sum is 43.

The spelling of 12128839261 in words is "twelve billion, one hundred twenty-eight million, eight hundred thirty-nine thousand, two hundred sixty-one".