12867217785 has 24 divisors (see below), whose sum is σ = 23072254920. Its totient is φ = 6625876992.

The previous prime is 12867217763. The next prime is 12867217787. The reversal of 12867217785 is 58771276821.

It can be written as a sum of positive squares in 4 ways, for example, as 3224763369 + 9642454416 = 56787^2 + 98196^2 .

It is not a de Polignac number, because 12867217785 - 2¹⁴ = 12867201401 is a prime.

It is a super-3 number, since 3×12867217785³ (a number of 31 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (12867217787) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4928664 + ... + 4931273.

It is an arithmetic number, because the mean of its divisors is an integer number (961343955).

Almost surely, 2^12867217785 is an apocalyptic number.

12867217785 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

12867217785 is a deficient number, since it is larger than the sum of its proper divisors (10205037135).

12867217785 is a wasteful number, since it uses less digits than its factorization.

12867217785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9859977 (or 9859974 counting only the distinct ones).

The product of its digits is 2634240, while the sum is 54.

The spelling of 12867217785 in words is "twelve billion, eight hundred sixty-seven million, two hundred seventeen thousand, seven hundred eighty-five".