381187 has 4 divisors (see below), whose sum is σ = 385560. Its totient is φ = 376816.

The previous prime is 381181. The next prime is 381209. The reversal of 381187 is 781183.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 781183 = 13 ⋅60091.

It is a cyclic number.

It is not a de Polignac number, because 381187 - 2¹⁵ = 348419 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (381181) 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, 2053 + ... + 2230.

It is an arithmetic number, because the mean of its divisors is an integer number (96390).

2³⁸¹¹⁸⁷ is an apocalyptic number.

381187 is a deficient number, since it is larger than the sum of its proper divisors (4373).

381187 is an equidigital number, since it uses as much as digits as its factorization.

381187 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4372.

The product of its digits is 1344, while the sum is 28.

The square root of 381187 is about 617.4034337449. The cubic root of 381187 is about 72.5069038214.

It can be divided in two parts, 38 and 1187, that added together give a triangular number (1225 = T₄₉).

The spelling of 381187 in words is "three hundred eighty-one thousand, one hundred eighty-seven".