• 450 can be written using four 4's:

See also 113.

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450 has 18 divisors (see below), whose sum is σ = 1209. Its totient is φ = 120.

The previous prime is 449. The next prime is 457. The reversal of 450 is 54.

450 is nontrivially palindromic in base 14.

450 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

450 is an esthetic number in base 7, because in such base its adjacent digits differ by 1.

It can be written as a sum of positive squares in 2 ways, for example, as 441 + 9 = 21^2 + 3^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=15.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is an alternating number because its digits alternate between even and odd.

450 is an undulating number in base 7 and base 14.

It is a plaindrome in base 11 and base 13.

It is a nialpdrome in base 5, base 9 and base 15.

It is a zygodrome in base 5.

It is not an unprimeable number, because it can be changed into a prime (457) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 88 + ... + 92.

It is a practical number, because each smaller number is the sum of distinct divisors of 450

450 is an abundant number, since it is smaller than the sum of its proper divisors (759).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

450 is a wasteful number, since it uses less digits than its factorization.

450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18 (or 10 counting only the distinct ones).

The product of its (nonzero) digits is 20, while the sum is 9.

The square root of 450 is about 21.2132034356. The cubic root of 450 is about 7.6630943239.

The spelling of 450 in words is "four hundred fifty", and thus it is an aban number.