1688960881 has 2 divisors, whose sum is σ = 1688960882. Its totient is φ = 1688960880.

The previous prime is 1688960873. The next prime is 1688960887. The reversal of 1688960881 is 1880698861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 942797025 + 746163856 = 30705^2 + 27316^2 .

It is an emirp because it is prime and its reverse (1880698861) is a distict prime. It is also a bemirp because it and its reverse can be mirrored producing other two distinct primes, 1880968891 and 1988690881.

It is a cyclic number.

It is not a de Polignac number, because 1688960881 - 2³ = 1688960873 is a prime.

It is a super-2 number, since 2×1688960881² = 5705177715096592322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1688960887) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 844480440 + 844480441.

It is an arithmetic number, because the mean of its divisors is an integer number (844480441).

Almost surely, 2^1688960881 is an apocalyptic number.

It is an amenable number.

1688960881 is a deficient number, since it is larger than the sum of its proper divisors (1).

1688960881 is an equidigital number, since it uses as much as digits as its factorization.

1688960881 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1327104, while the sum is 55.

The square root of 1688960881 is about 41096.9692434856. The cubic root of 1688960881 is about 1190.8942460376.

The spelling of 1688960881 in words is "one billion, six hundred eighty-eight million, nine hundred sixty thousand, eight hundred eighty-one".