How do you factorize #1244244282442#?

1 Answer
Jan 26, 2017

#1244244282442=2xx7xx7xx421xx30157649#

Explanation:

It is apparent that #1244244282442# is divisible by #2# and dividing by #2# one gets #622122141221#.

Divisibility of #7# is somewhat complicated and according to it you have to double the last digit and subtract it from a number made by the other digits. However, as #62212214120# is divisible by #7# and as such #622122141221# too is divisibile by #7# and dividing by #7# one gets #88874591603#, which is again divisible by #7# and dividing we get #12696370229#.

Hence #1244244282442=12696370229xx98#

It may be worth mentioning that may be #12696370229# can be factorized further, but the same may not be easy and may require computing power. In fact while it is easy to multiply two large primes to get a number, it is not easy to do the reverse process and it is mainly on this premise that famous RSA based encryption system is used.

Post script - #12696370229# is further divisible by #421# as

#12696370229=421xx30157649#

and #30157649# is a prime number. One can check it at http://www.onlineconversion.com/prime.htm

Hence #1244244282442=2xx7xx7xx421xx30157649#