688565897 has 2 divisors, whose sum is σ = 688565898. Its totient is φ = 688565896.

The previous prime is 688565873. The next prime is 688565903. The reversal of 688565897 is 798565886.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 559038736 + 129527161 = 23644^2 + 11381^2 .

It is a cyclic number.

It is not a de Polignac number, because 688565897 - 2⁸ = 688565641 is a prime.

It is a super-2 number, since 2×688565897² = 948245989022829218, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (688565497) 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, 344282948 + 344282949.

It is an arithmetic number, because the mean of its divisors is an integer number (344282949).

Almost surely, 2^688565897 is an apocalyptic number.

It is an amenable number.

688565897 is a deficient number, since it is larger than the sum of its proper divisors (1).

688565897 is an equidigital number, since it uses as much as digits as its factorization.

688565897 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 29030400, while the sum is 62.

The square root of 688565897 is about 26240.5391903444. The cubic root of 688565897 is about 883.0429680335.

The spelling of 688565897 in words is "six hundred eighty-eight million, five hundred sixty-five thousand, eight hundred ninety-seven".