12789281 has 4 divisors (see below), whose sum is σ = 12890112. Its totient is φ = 12688452.

The previous prime is 12789269. The next prime is 12789289. The reversal of 12789281 is 18298721.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18298721 = 7 ⋅2614103.

It is a cyclic number.

It is not a de Polignac number, because 12789281 - 2¹⁰ = 12788257 is a prime.

It is a super-2 number, since 2×12789281² = 327131416993922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12789289) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50225 + ... + 50478.

It is an arithmetic number, because the mean of its divisors is an integer number (3222528).

Almost surely, 2^12789281 is an apocalyptic number.

It is an amenable number.

12789281 is a deficient number, since it is larger than the sum of its proper divisors (100831).

12789281 is a wasteful number, since it uses less digits than its factorization.

12789281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100830.

The product of its digits is 16128, while the sum is 38.

The square root of 12789281 is about 3576.2104244577. The cubic root of 12789281 is about 233.8561038504.

The spelling of 12789281 in words is "twelve million, seven hundred eighty-nine thousand, two hundred eighty-one".