1688726329 has 2 divisors, whose sum is σ = 1688726330. Its totient is φ = 1688726328.

The previous prime is 1688726311. The next prime is 1688726339. The reversal of 1688726329 is 9236278861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1687566400 + 1159929 = 41080^2 + 1077^2 .

It is an emirp because it is prime and its reverse (9236278861) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1688726329 - 2⁷ = 1688726201 is a prime.

It is a super-2 number, since 2×1688726329² = 5703593228515632482, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1688726339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 844363164 + 844363165.

It is an arithmetic number, because the mean of its divisors is an integer number (844363165).

Almost surely, 2^1688726329 is an apocalyptic number.

It is an amenable number.

1688726329 is a deficient number, since it is larger than the sum of its proper divisors (1).

1688726329 is an equidigital number, since it uses as much as digits as its factorization.

1688726329 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1741824, while the sum is 52.

The square root of 1688726329 is about 41094.1155033175. The cubic root of 1688726329 is about 1190.8391155801.

The spelling of 1688726329 in words is "one billion, six hundred eighty-eight million, seven hundred twenty-six thousand, three hundred twenty-nine".