12691386 has 48 divisors (see below), whose sum is σ = 29189160. Its totient is φ = 3978240.

The previous prime is 12691381. The next prime is 12691387. The reversal of 12691386 is 68319621.

It can be written as a sum of positive squares in 4 ways, for example, as 8590761 + 4100625 = 2931^2 + 2025^2 .

It is a super-2 number, since 2×12691386² = 322142557201992, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 12691386.

It is not an unprimeable number, because it can be changed into a prime (12691381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 21106 + ... + 21698.

Almost surely, 2^12691386 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12691386, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14594580).

12691386 is an abundant number, since it is smaller than the sum of its proper divisors (16497774).

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

12691386 is a wasteful number, since it uses less digits than its factorization.

12691386 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 671 (or 668 counting only the distinct ones).

The product of its digits is 15552, while the sum is 36.

The square root of 12691386 is about 3562.4971578936. The cubic root of 12691386 is about 233.2578944334.

The spelling of 12691386 in words is "twelve million, six hundred ninety-one thousand, three hundred eighty-six".