688444873 has 2 divisors, whose sum is σ = 688444874. Its totient is φ = 688444872.

The previous prime is 688444871. The next prime is 688444907. The reversal of 688444873 is 378444886.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 687068944 + 1375929 = 26212^2 + 1173^2 .

It is a cyclic number.

It is not a de Polignac number, because 688444873 - 2¹ = 688444871 is a prime.

It is a super-2 number, since 2×688444873² = 947912686319972258, which contains 22 as substring.

Together with 688444871, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 688444873.

It is not a weakly prime, because it can be changed into another prime (688444871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344222436 + 344222437.

It is an arithmetic number, because the mean of its divisors is an integer number (344222437).

Almost surely, 2^688444873 is an apocalyptic number.

It is an amenable number.

688444873 is a deficient number, since it is larger than the sum of its proper divisors (1).

688444873 is an equidigital number, since it uses as much as digits as its factorization.

688444873 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4128768, while the sum is 52.

The square root of 688444873 is about 26238.2330388309. The cubic root of 688444873 is about 882.9912297494.

The spelling of 688444873 in words is "six hundred eighty-eight million, four hundred forty-four thousand, eight hundred seventy-three".