381989 has 2 divisors, whose sum is σ = 381990. Its totient is φ = 381988.

The previous prime is 381977. The next prime is 381991. The reversal of 381989 is 989183.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 209764 + 172225 = 458^2 + 415^2 .

It is a cyclic number.

It is not a de Polignac number, because 381989 - 2¹⁶ = 316453 is a prime.

It is a super-2 number, since 2×381989² = 291831192242, which contains 22 as substring.

Together with 381991, it forms a pair of twin primes.

It is a Chen prime.

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 381989.

It is not a weakly prime, because it can be changed into another prime (381949) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 190994 + 190995.

It is an arithmetic number, because the mean of its divisors is an integer number (190995).

2³⁸¹⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

381989 is a deficient number, since it is larger than the sum of its proper divisors (1).

381989 is an equidigital number, since it uses as much as digits as its factorization.

381989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 38.

The square root of 381989 is about 618.0525867594. The cubic root of 381989 is about 72.5577186029.

The spelling of 381989 in words is "three hundred eighty-one thousand, nine hundred eighty-nine".