The hex color #615C92 is a dark color. The web-safe version is Hex
#666699. A complementary color is
#9EA36D. The grayscale version is
#707070. A 20% lighter version of the original color is
#948FC5, and Hex
#2E295F is the 20% darker color. If the color is saturated by 10%, you get
#605A95. If the color is desaturated by 10%, the color
#625E8F is obtained.