Answer based on context:

According to 2011 census of India, Gobichettipalayam had a population of 60,279 with a sex-ratio of 1,062 females for every 1,000 males, much above the national average of 929. A total of 4,669 were under the age of six, constituting 2,364 males and 2,305 females. Scheduled Castes and Scheduled Tribes accounted for 10.74% and .08% of the population respectively. The average literacy of the city was 78.52%, compared to the national average of 72.99%. The city had a total of 17064 households. There were a total of 25,225 workers, comprising 512 cultivators, 2,035 main agricultural labourers, 637 in house hold industries, 21,070 other workers, 971 marginal workers, 15 marginal cultivators, 308 marginal agricultural labourers, 57 marginal workers in household industries and 591 other marginal workers.

How many more main agricultural labourers were there compared to cultivators and marginal cultivators combined?
1508