• 1378² = 1898884 is the smallest square that contains exactly four digits '8'.

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1378 has 8 divisors (see below), whose sum is σ = 2268. Its totient is φ = 624.

The previous prime is 1373. The next prime is 1381. The reversal of 1378 is 8731.

1378 is a nontrivial binomial coefficient, being equal to C(53, 2).

It can be written as a sum of positive squares in 2 ways, for example, as 1369 + 9 = 37^2 + 3^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a plaindrome in base 10.

It is a nialpdrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (1373) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1 + ... + 52.

1378 is the 52-nd triangular number.

1378 is the 18-th centered nonagonal number.

1378 is a deficient number, since it is larger than the sum of its proper divisors (890).

1378 is a wasteful number, since it uses less digits than its factorization.

1378 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68.

The product of its digits is 168, while the sum is 19.

The square root of 1378 is about 37.1214223865. The cubic root of 1378 is about 11.1279817787.

It can be divided in two parts, 13 and 78, that added together give a triangular number (91 = T₁₃).

The spelling of 1378 in words is "one thousand, three hundred seventy-eight".