381188 has 12 divisors (see below), whose sum is σ = 671580. Its totient is φ = 189312.

The previous prime is 381181. The next prime is 381209. The reversal of 381188 is 881183.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 222784 + 158404 = 472^2 + 398^2 .

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 381188.

It is not an unprimeable number, because it can be changed into a prime (381181) by changing a digit.

381188 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 3 ways as a sum of consecutive naturals, for example, 728 + ... + 1136.

It is an arithmetic number, because the mean of its divisors is an integer number (55965).

2³⁸¹¹⁸⁸ is an apocalyptic number.

It is an amenable number.

381188 is a deficient number, since it is larger than the sum of its proper divisors (290392).

381188 is a wasteful number, since it uses less digits than its factorization.

381188 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 646 (or 644 counting only the distinct ones).

The product of its digits is 1536, while the sum is 29.

The square root of 381188 is about 617.4042435876. The cubic root of 381188 is about 72.5069672258.

The spelling of 381188 in words is "three hundred eighty-one thousand, one hundred eighty-eight".