12891312 has 200 divisors, whose sum is σ = 45012000. Its totient is φ = 3556224.

The previous prime is 12891259. The next prime is 12891353. The reversal of 12891312 is 21319821.

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

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 444514 + ... + 444542.

It is an arithmetic number, because the mean of its divisors is an integer number (225060).

Almost surely, 2^12891312 is an apocalyptic number.

12891312 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12891312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22506000).

12891312 is an abundant number, since it is smaller than the sum of its proper divisors (32120688).

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

12891312 is an equidigital number, since it uses as much as digits as its factorization.

12891312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70 (or 41 counting only the distinct ones).

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

The square root of 12891312 is about 3590.4473258913. The cubic root of 12891312 is about 234.4763472097.

It can be divided in two parts, 12891 and 312, that added together give a triangular number (13203 = T₁₆₂).

The spelling of 12891312 in words is "twelve million, eight hundred ninety-one thousand, three hundred twelve".