381312 has 48 divisors (see below), whose sum is σ = 1100580. Its totient is φ = 126720.

The previous prime is 381301. The next prime is 381319. The reversal of 381312 is 213183.

It is a tau number, because it is divible by the number of its divisors (48).

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

It is a nude number because it is divisible by every one of its digits and also a Zuckerman number because it is divisible by the product of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (381319) by changing a digit.

381312 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 (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 987 + ... + 1317.

2³⁸¹³¹² is an apocalyptic number.

381312 is a gapful number since it is divisible by the number (32) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 381312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (550290).

381312 is an abundant number, since it is smaller than the sum of its proper divisors (719268).

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

381312 is a wasteful number, since it uses less digits than its factorization.

381312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 351 (or 336 counting only the distinct ones).

The product of its digits is 144, while the sum is 18.

The square root of 381312 is about 617.5046558529. The cubic root of 381312 is about 72.5148285166.

Adding to 381312 its reverse (213183), we get a palindrome (594495).

The spelling of 381312 in words is "three hundred eighty-one thousand, three hundred twelve".