1681867469 has 2 divisors, whose sum is σ = 1681867470. Its totient is φ = 1681867468.

The previous prime is 1681867399. The next prime is 1681867489. The reversal of 1681867469 is 9647681861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 906913225 + 774954244 = 30115^2 + 27838^2 .

It is an emirp because it is prime and its reverse (9647681861) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1681867469 is a prime.

It is a super-2 number, since 2×1681867469² = 5657356366560931922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1681867489) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 840933734 + 840933735.

It is an arithmetic number, because the mean of its divisors is an integer number (840933735).

Almost surely, 2^1681867469 is an apocalyptic number.

It is an amenable number.

1681867469 is a deficient number, since it is larger than the sum of its proper divisors (1).

1681867469 is an equidigital number, since it uses as much as digits as its factorization.

1681867469 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3483648, while the sum is 56.

The square root of 1681867469 is about 41010.5775258042. The cubic root of 1681867469 is about 1189.2247072039.

The spelling of 1681867469 in words is "one billion, six hundred eighty-one million, eight hundred sixty-seven thousand, four hundred sixty-nine".