Find the odd number / letters / word from the given alternative:

29
53
85
125 E. 147

The odd number in the given list is 147. All the other numbers are prime numbers, while 147 is a composite number.

A prime number is a natural number greater than 1 that is not a product of two smaller natural numbers. A natural number greater than 1 that is not prime is called a composite number.

29, 53, and 85 are all prime numbers because they are not divisible by any number other than themselves and 1. 125 is a composite number because it is divisible by 5 and 25.