Square digit chains : Problem 92 : Project Euler

Square digit chains : Problem 92 : Project Euler

A number chain is created by continuously adding the square of the digits in a number to form a new number until it has been seen before.
For example,

44 → 32 → 13 → 10 → 1 → 1
85 → 89 → 145 → 42 → 20 → 4 → 16 → 37 → 58 → 89

Therefore any chain that arrives at 1 or 89 will become stuck in an endless loop. What is most amazing is that EVERY starting number will eventually arrive at 1 or 89.
How many starting numbers below ten million will arrive at 89?

Python Code

def squareDigitChains():
    squareDigitCount = 0
    for i in range(1,10000000):
        strnumber = ""
        strnumber = str(i)
        sqnumber = 0
        temp = strnumber
        while True:
            sqnumber = 0
            for j in range(len(strnumber)):
                sqnumber = sqnumber + int(strnumber[j])**2
            strnumber = str(sqnumber)   
            if sqnumber == 1 or sqnumber == 89:
                break
        if sqnumber == 89:
            print temp
            squareDigitCount = squareDigitCount + 1
    print "Required Counter is:",squareDigitCount               
squareDigitChains()