• 378 can be written using four 4's:

See also 113.

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378 has 16 divisors (see below), whose sum is σ = 960. Its totient is φ = 108.

The previous prime is 373. The next prime is 379. The reversal of 378 is 873.

378 is nontrivially palindromic in base 5.

378 is a nontrivial binomial coefficient, being equal to C(28, 2).

It is a Smith number, since the sum of its digits (18) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a d-powerful number, because it can be written as 3³ + 7³ + 8 .

It is a cake number, because a cake can be divided into 378 parts by 13 planar cuts.

Its product of digits (168) is a multiple of the sum of its prime divisors (12).

It is a Curzon number.

It is a plaindrome in base 10 and base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 378.

It is not an unprimeable number, because it can be changed into a prime (373) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 51 + ... + 57.

It is an arithmetic number, because the mean of its divisors is an integer number (60).

378 is the 27-th triangular number and also the 14-th hexagonal number.

It is a practical number, because each smaller number is the sum of distinct divisors of 378, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (480).

378 is an abundant number, since it is smaller than the sum of its proper divisors (582).

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

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

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

The sum of its prime factors is 18 (or 12 counting only the distinct ones).

The product of its digits is 168, while the sum is 18.

The square root of 378 is about 19.4422220952. The cubic root of 378 is about 7.2304267925.

378 divided by its sum of digits (18) gives a triangular number (21 = T₆).

Subtracting from 378 its product of digits (168), we obtain a triangular number (210 = T₂₀).

Multiplying 378 by its product of digits (168), we get a square (63504 = 252²).

It can be divided in two parts, 37 and 8, that added together give a triangular number (45 = T₉).

The spelling of 378 in words is "three hundred seventy-eight", and thus it is an aban number and an oban number.