整个 (zhěng gè) means 'the whole (of a single entity)' and is used directly before a noun (e.g., 整个公司 'the whole company'). It emphasizes one complete unit. 全 (quán) can also mean 'whole' but is more general and can refer to 'all' (multiple items); 整 (zhěng) focuses on being 'complete' or 'intact' and is often used as a prefix (e.g., 整天 'the whole day').