This number is a composite.

+ The smallest composite number whose digits are composite such that the concatenated factors of either digit with the remaining digit(s) is prime. [Rivera]

+ The first 49 digits after the decimal point in e = 2.718... form a prime. [Honaker]

+ The largest prime square which is greater than the product of all lesser primes. [Murthy]

+ The smallest semiprime whose sum of divisors is also a semiprime. [Gupta]

+ phi(49)*49^49 + 1 is prime. The reversal of 49 has the same property. [Firoozbakht]

+ The smallest square that is the sum of three consecutive primes. [Silva]

+ The smallest prime square that is the sum of consecutive composite numbers in three ways, i.e., 24+25 = 15+16+18 = 4+6+8+9+10+12 = 7^2. [Loungrides]

+ 100^49 + 49 is the largest non-titanic prime of form 100^n + n. [Loungrides]

+ 49 is the smallest April Fools prime whose sum of digits is not divisible by π(-4+9). [Worrom]

(There are 12 curios for this number that have not yet been approved by an editor.)

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