688271449 has 2 divisors, whose sum is σ = 688271450. Its totient is φ = 688271448.

The previous prime is 688271359. The next prime is 688271477. The reversal of 688271449 is 944172886.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 491065600 + 197205849 = 22160^2 + 14043^2 .

It is a cyclic number.

It is not a de Polignac number, because 688271449 - 2⁷ = 688271321 is a prime.

It is not a weakly prime, because it can be changed into another prime (688272449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344135724 + 344135725.

It is an arithmetic number, because the mean of its divisors is an integer number (344135725).

Almost surely, 2^688271449 is an apocalyptic number.

It is an amenable number.

688271449 is a deficient number, since it is larger than the sum of its proper divisors (1).

688271449 is an equidigital number, since it uses as much as digits as its factorization.

688271449 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 774144, while the sum is 49.

The square root of 688271449 is about 26234.9280349690. The cubic root of 688271449 is about 882.9170796675.

The spelling of 688271449 in words is "six hundred eighty-eight million, two hundred seventy-one thousand, four hundred forty-nine".