1687268689 has 2 divisors, whose sum is σ = 1687268690. Its totient is φ = 1687268688.

The previous prime is 1687268641. The next prime is 1687268711. The reversal of 1687268689 is 9868627861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1176147025 + 511121664 = 34295^2 + 22608^2 .

It is a cyclic number.

It is not a de Polignac number, because 1687268689 - 2¹¹ = 1687266641 is a prime.

It is not a weakly prime, because it can be changed into another prime (1687268629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 843634344 + 843634345.

It is an arithmetic number, because the mean of its divisors is an integer number (843634345).

Almost surely, 2^1687268689 is an apocalyptic number.

It is an amenable number.

1687268689 is a deficient number, since it is larger than the sum of its proper divisors (1).

1687268689 is an equidigital number, since it uses as much as digits as its factorization.

1687268689 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13934592, while the sum is 61.

The square root of 1687268689 is about 41076.3762885676. The cubic root of 1687268689 is about 1190.4963889609.

The spelling of 1687268689 in words is "one billion, six hundred eighty-seven million, two hundred sixty-eight thousand, six hundred eighty-nine".