12687840 has 240 divisors, whose sum is σ = 49397040. Its totient is φ = 3041280.

The previous prime is 12687823. The next prime is 12687841. The reversal of 12687840 is 4878621.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a zygodrome in base 2.

It is a junction number, because it is equal to n+sod(n) for n = 12687795 and 12687804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12687841) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 142516 + ... + 142604.

It is an arithmetic number, because the mean of its divisors is an integer number (205821).

Almost surely, 2^12687840 is an apocalyptic number.

12687840 is a gapful number since it is divisible by the number (10) 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 12687840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24698520).

12687840 is an abundant number, since it is smaller than the sum of its proper divisors (36709200).

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

12687840 is a wasteful number, since it uses less digits than its factorization.

12687840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127 (or 110 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 12687840 is about 3561.9994385176. Note that the first 3 decimals coincide. The cubic root of 12687840 is about 233.2361681607.

The spelling of 12687840 in words is "twelve million, six hundred eighty-seven thousand, eight hundred forty".