It is a primorial, being the product of the first 3 primes.
30 is nontrivially palindromic in base 9 and base 14.
30 is an esthetic number in base 3, because in such base its adjacent digits differ by 1.
It is a sphenic number, since it is the product of 3 distinct primes.
30 is an admirable number.
It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.
30 is an idoneal number.
It is an alternating number because its digits alternate between odd and even.
30 is an undulating number in base 3.
It is a Curzon number.
30 is a nontrivial repdigit in base 9 and base 14.
It is a plaindrome in base 8, base 9, base 11, base 12, base 13, base 14 and base 16.
It is a nialpdrome in base 2, base 5, base 6, base 7, base 9, base 10, base 14 and base 15.
It is a zygodrome in base 9 and base 14.
It is a congruent number.
A polygon with 30 sides can be constructed with ruler and compass.
30 is a Giuga number.
30 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
30 is a wasteful number, since it uses less digits than its factorization.
30 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 10.
The square root of 30 is about 5.4772255751. The cubic root of 30 is about 3.1072325060.