Cash value in life insurance is the amount remaining after you submit your premium payment to your insurance company and the carrier takes out any cost of insurance and mortality & expense charges.
There is no exact figure for it as it will vary by policy – your face amount, length of coverage, risk class, premiums, and other factors go into the calculation. The cost of insurance/mortality & expense charges on permanent policies will vary from carrier to carrier as well as whether the policy is a Universal or Whole life policy.
The cash value can be borrowed against (acting like a loan with interest rates and the expectation to be paid back – when not paid back, the outstanding balance of the loan is deducted from the death benefit and the beneficiary receives the difference), or pay your premiums for you.