Yes! If it finds the number itself:

Code:

**~$** echo 2047 | ecm -one 1000
GMP-ECM 7.0.4 [configured with GMP 6.2.0, --enable-asm-redc] [ECM]
Input number is 2047 (4 digits)
Using B1=1000, B2=51606, polynomial x^1, sigma=1:2307810929
Step 1 took 1ms
********** Factor found in step 1: 2047
Found input number N
**~$** echo $?
8

If it finds a factor and the cofactor is prime (maybe PRP):

Code:

**~$** echo 2047 | ecm -one 1
GMP-ECM 7.0.4 [configured with GMP 6.2.0, --enable-asm-redc] [ECM]
Input number is 2047 (4 digits)
Using B1=1, B2=12, polynomial x^1, sigma=1:309160743
Step 1 took 0ms
Step 2 took 0ms
********** Factor found in step 2: 23
Found prime factor of 2 digits: 23
Prime cofactor 89 has 2 digits
**~$** echo $?
14

If it finds a factor and the cofactor is composite:

Code:

**~$** echo '2*(2^2047-1)' | ecm -one 1
GMP-ECM 7.0.4 [configured with GMP 6.2.0, --enable-asm-redc] [ECM]
Input number is 2*(2^2047-1) (617 digits)
********** Factor found in step 1: 2
Found prime factor of 1 digits: 2
Composite cofactor (2*(2^2047-1))/2 has 617 digits
**~$** echo $?
6

I'd have to look into the code if there are other possibilities.