381636 has 18 divisors (see below), whose sum is σ = 964782. Its totient is φ = 127200.

The previous prime is 381631. The next prime is 381637. The reversal of 381636 is 636183.

It can be written as a sum of positive squares in only one way, i.e., 367236 + 14400 = 606^2 + 120^2 .

It is a tau number, because it is divible by the number of its divisors (18).

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

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 381636.

It is not an unprimeable number, because it can be changed into a prime (381631) by changing a digit.

381636 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5265 + ... + 5336.

It is an arithmetic number, because the mean of its divisors is an integer number (53599).

2³⁸¹⁶³⁶ is an apocalyptic number.

381636 is a gapful number since it is divisible by the number (36) formed by its first and last digit.

It is an amenable number.

381636 is an abundant number, since it is smaller than the sum of its proper divisors (583146).

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

381636 is a wasteful number, since it uses less digits than its factorization.

381636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10611 (or 10606 counting only the distinct ones).

The product of its digits is 2592, while the sum is 27.

The square root of 381636 is about 617.7669463479. The cubic root of 381636 is about 72.5353612677.

The spelling of 381636 in words is "three hundred eighty-one thousand, six hundred thirty-six".