12783989 has 4 divisors (see below), whose sum is σ = 12797100. Its totient is φ = 12770880.

The previous prime is 12783977. The next prime is 12784007. The reversal of 12783989 is 98938721.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98938721 = 7 ⋅14134103.

It can be written as a sum of positive squares in 2 ways, for example, as 8614225 + 4169764 = 2935^2 + 2042^2 .

It is a cyclic number.

It is not a de Polignac number, because 12783989 - 2⁴ = 12783973 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12783919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4964 + ... + 7085.

It is an arithmetic number, because the mean of its divisors is an integer number (3199275).

Almost surely, 2^12783989 is an apocalyptic number.

It is an amenable number.

12783989 is a deficient number, since it is larger than the sum of its proper divisors (13111).

12783989 is a wasteful number, since it uses less digits than its factorization.

12783989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13110.

The product of its digits is 217728, while the sum is 47.

The square root of 12783989 is about 3575.4704585551. The cubic root of 12783989 is about 233.8238440948.

The spelling of 12783989 in words is "twelve million, seven hundred eighty-three thousand, nine hundred eighty-nine".