To see the details of all the nodes you can use:

scontrol show node

To see jobs' info including number of nodes and cores you can use the format mark %C, for instance:

squeue -o"%.7i %.9P %.8j %.8u %.2t %.10M %.6D %C"

  JOBID PARTITION     NAME     USER ST       TIME  NODES CPUS
 197736  AMG-long      clc v.logvin PD       0:00      1 1
 197737  AMG-long      clc v.logvin PD       0:00      1 1
 197735  AMG-long      clc v.logvin  R       3:50      1 1
 197734  AMG-long      clc v.logvin  R      40:40      1 1
 197732  AMG-long      clc v.logvin  R      47:56      1 1
 197696 AMG-mediu heat_100 a.dembit  R    5:55:25      1 8
 197695 AMG-mediu heat_800 a.dembit  R    5:58:56      1 8
 197697 AMG-mediu heat_120 a.dembit  R    5:38:49      1 8
 197739 AMG-mediu heat_600 a.dembit  R      12:24      1 16
 197675  AMG-long Na2Fe2C6 o.kovaly  R   10:40:39      1 8
 197738  AMG-long Fe2C6N6. o.kovaly  R      14:51      1 8
 197667 AMG-mediu lvp.010.  a.burov  R   18:18:39      1 8
 197666 AMG-mediu lvp.010.  a.burov  R 1-21:55:06      1 8
 197731 AMG-mediu llzo_int  a.burov  R    1:49:13      1 8
 197730 AMG-mediu llzo_int  a.burov  R    1:49:34      1 8
 197663  AMG-long lvp.na.o  a.burov  R 1-21:58:36      1 16