Sum of six consecutive primes (3 + 5 + 7 + 11 + 13 + 17)

Sum of the first six triangular numbers (1 + 3 + 6 + 10 + 15 + 21)

Sum of the divisors of the first 8 positive integers

Maximum determinant in an 8 by 8 matrix of zeroes and ones

Only known number n such that φ(n-1)σ(n-1) = φ(n)σ(n) = φ(n+1)σ(n+1), where φ is Euler’s totient function and σ is the sum of the divisor function

Number of bits in a key used in the Data Encryption Standard

Number of signatories of United States Declaration of Independence

Number of curls in Shirley Temple’s hair

Much more personal significance, besides my current age, the atomic number of barium – no wonder I don’t lose weight! #GreekEtymologyJoke

[image generated by a 56-line script, using 56 open source fonts]