12786817649956 has 27 divisors (see below), whose sum is σ = 26030409271419. Its totient is φ = 5480043251928.

The previous prime is 12786817649909. The next prime is 12786817649999. The reversal of 12786817649956 is 65994671868721.

The square root of 12786817649956 is 3575866.

It is a perfect power (a square), and thus also a powerful number.

It is a super-3 number, since 3×12786817649956³ (a number of 40 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 49934415 + ... + 50189833.

Almost surely, 2^{12786817649956} is an apocalyptic number.

12786817649956 is the 3575866-th square number.

It is an amenable number.

12786817649956 is an abundant number, since it is smaller than the sum of its proper divisors (13243591621463).

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

12786817649956 is an frugal number, since it uses more digits than its factorization.

12786817649956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 510856 (or 255428 counting only the distinct ones).

The product of its digits is 2194698240, while the sum is 79.

The spelling of 12786817649956 in words is "twelve trillion, seven hundred eighty-six billion, eight hundred seventeen million, six hundred forty-nine thousand, nine hundred fifty-six".