907
This number is a prime.
907, 9907, 99907, 999907, and 9999907 are all primes; however, 99999907 is composite.
The molecular weight of chlorophyll b is about 907. [Wu]
Conjectured to be the largest prime that can be represented uniquely as the sum of three distinct positive squares (32 + 132 + 272). [Noe]
The largest negated discriminant of imaginary quadratic fields with class number 3. There are 16 = 9+0+7 such discriminants. [Hasler]
The largest area code (in physical size) in the United States. It covers the entire state of Alaska, except for the small southeastern community of Hyder. [Green]
According to Hindu mythology, a great sage ("Kandu") once fell for and romanced with a celestial nymph ("Pramlocha") for 907 years before he came back to his senses and realized he had gone astray. [Beedassy]
The smallest prime number of the form a^b + c^d + e^f + g^h + i^j where each letter represents a different single digit number (1^7 + 5^4 + 6^3 + 8^2 + 9^0). [Gaydos]