381281 has 4 divisors (see below), whose sum is σ = 390192. Its totient is φ = 372372.

The previous prime is 381253. The next prime is 381287. The reversal of 381281 is 182183.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-381281 is a prime.

It is a super-2 number, since 2×381281² = 290750401922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 381281.

It is not an unprimeable number, because it can be changed into a prime (381287) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4391 + ... + 4476.

It is an arithmetic number, because the mean of its divisors is an integer number (97548).

2³⁸¹²⁸¹ is an apocalyptic number.

It is an amenable number.

381281 is a deficient number, since it is larger than the sum of its proper divisors (8911).

381281 is an equidigital number, since it uses as much as digits as its factorization.

381281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8910.

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

The square root of 381281 is about 617.4795543174. The cubic root of 381281 is about 72.5128633537.

The spelling of 381281 in words is "three hundred eighty-one thousand, two hundred eighty-one".