389687281 has 2 divisors, whose sum is σ = 389687282. Its totient is φ = 389687280.

The previous prime is 389687261. The next prime is 389687303. The reversal of 389687281 is 182786983.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 266832225 + 122855056 = 16335^2 + 11084^2 .

It is a cyclic number.

It is not a de Polignac number, because 389687281 - 2¹⁹ = 389162993 is a prime.

It is a super-2 number, since 2×389687281² = 303712353946345922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (389687231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 194843640 + 194843641.

It is an arithmetic number, because the mean of its divisors is an integer number (194843641).

Almost surely, 2^389687281 is an apocalyptic number.

It is an amenable number.

389687281 is a deficient number, since it is larger than the sum of its proper divisors (1).

389687281 is an equidigital number, since it uses as much as digits as its factorization.

389687281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1161216, while the sum is 52.

The square root of 389687281 is about 19740.4984992781. The cubic root of 389687281 is about 730.4190257088.

The spelling of 389687281 in words is "three hundred eighty-nine million, six hundred eighty-seven thousand, two hundred eighty-one".