Cerulean (#007BA7) is a medium, highly saturated blue hue. Cerulean is a deep sky blue; the name comes from the Latin for heaven.
In RGB it is made of 0 red, 123 green and 167 blue. Its HSL hue angle is 196° with 100% saturation and 33% lightness, while its perceptual OKLCH lightness is 55% with a chroma of 0.112. For print, a starting CMYK mix is 100% cyan, 26% magenta, 0% yellow and 35% black.
As a text color on white, Cerulean has a contrast ratio of 4.78:1, which passes WCAG AA for normal text. On black it reaches 4.39:1 and passes AA only for large text. If you use Cerulean as a background, put white text on it. The APCA lightness contrast is Lc 32 for black text and Lc -78 for white text.
Its perceptual complement is #A35C2B, close to brown. Colors that look most similar are steel blue, teal, denim. It looks fairly similar to people with red-green color blindness (ΔE 6), so its meaning mostly survives.