12911820 has 24 divisors (see below), whose sum is σ = 36153264. Its totient is φ = 3443136.

The previous prime is 12911819. The next prime is 12911851. The reversal of 12911820 is 2811921.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 107539 + ... + 107658.

It is an arithmetic number, because the mean of its divisors is an integer number (1506386).

Almost surely, 2^12911820 is an apocalyptic number.

12911820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12911820 is an abundant number, since it is smaller than the sum of its proper divisors (23241444).

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

12911820 is a wasteful number, since it uses less digits than its factorization.

12911820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 215209 (or 215207 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 24.

The square root of 12911820 is about 3593.3021025235. The cubic root of 12911820 is about 234.6006193617.

It can be divided in two parts, 12911 and 820, that added together give a palindrome (13731).

The spelling of 12911820 in words is "twelve million, nine hundred eleven thousand, eight hundred twenty".