1681867489 has 2 divisors, whose sum is σ = 1681867490. Its totient is φ = 1681867488.

The previous prime is 1681867469. The next prime is 1681867501. The reversal of 1681867489 is 9847681861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 890007889 + 791859600 = 29833^2 + 28140^2 .

It is an emirp because it is prime and its reverse (9847681861) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1681867489 - 2⁷ = 1681867361 is a prime.

It is not a weakly prime, because it can be changed into another prime (1681867469) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 840933744 + 840933745.

It is an arithmetic number, because the mean of its divisors is an integer number (840933745).

Almost surely, 2^1681867489 is an apocalyptic number.

It is an amenable number.

1681867489 is a deficient number, since it is larger than the sum of its proper divisors (1).

1681867489 is an equidigital number, since it uses as much as digits as its factorization.

1681867489 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4644864, while the sum is 58.

The square root of 1681867489 is about 41010.5777696438. The cubic root of 1681867489 is about 1189.2247119178.

The spelling of 1681867489 in words is "one billion, six hundred eighty-one million, eight hundred sixty-seven thousand, four hundred eighty-nine".