381812 has 12 divisors (see below), whose sum is σ = 681156. Its totient is φ = 187200.

The previous prime is 381793. The next prime is 381817. The reversal of 381812 is 218183.

381812 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 155236 + 226576 = 394^2 + 476^2 .

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (381817) by changing a digit.

381812 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 689 + ... + 1112.

It is an arithmetic number, because the mean of its divisors is an integer number (56763).

2³⁸¹⁸¹² is an apocalyptic number.

It is an amenable number.

381812 is a deficient number, since it is larger than the sum of its proper divisors (299344).

381812 is a wasteful number, since it uses less digits than its factorization.

381812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1858 (or 1856 counting only the distinct ones).

The product of its digits is 384, while the sum is 23.

The square root of 381812 is about 617.9093784690. The cubic root of 381812 is about 72.5465099902.

Adding to 381812 its reverse (218183), we get a palindrome (599995).

It can be divided in two parts, 38181 and 2, that added together give a palindrome (38183).

The spelling of 381812 in words is "three hundred eighty-one thousand, eight hundred twelve".