[[135]] is not prime (composite). Want proof? :)

Full prime factorization: [[3]] * [[3]] * [[3]] * [[5]]

Factor pairs:

[[135]] = [[3]] * [[45]]

[[135]] = [[5]] * [[27]]

[[135]] = [[9]] * [[15]]

Proper divisors: [[3]], [[5]], [[9]], [[15]], [[27]], [[45]]

Primes up to 135: [[2]], [[3]], [[5]], [[7]], [[11]], [[13]], [[17]], [[19]], [[23]], [[29]], [[31]], [[37]], [[41]], [[43]], [[47]], [[53]], [[59]], [[61]], [[67]], [[71]], [[73]], [[79]], [[83]], [[89]], [[97]], [[101]], [[103]], [[107]], [[109]], [[113]], [[127]], [[131]].

[[135]] is not a centered hexagonal number.

The closest centered hexagonal numbers are [[127]] (index # [[7]]) and [[169]] (index # [[8]]).

First 20 centered hexagonal numbers: [[1]], [[7]], [[19]], [[37]], [[61]], [[91]], [[127]], [[169]], [[217]], [[271]], [[331]], [[397]], [[469]], [[547]], [[631]], [[721]], [[817]], [[919]], [[1027]], [[1141]].

[[hz/135]] is closest to [[C#3]] at [[135]] Hz (-45 cents).

Note class: [[C#]], Octave: [[octave/3]].

• [[square]]: 18225

• [[square root]]: 11.6190

• [[cube]]: 2460375

• [[cube root]]: 5.1299

• [[natural log]] (ln): 4.9053

• [[base-10 log]] (log10): 2.1303

• [[base-2 log]] (log2): 7.0768