688905071 has 2 divisors, whose sum is σ = 688905072. Its totient is φ = 688905070.

The previous prime is 688905053. The next prime is 688905073. The reversal of 688905071 is 170509886.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 688905071 - 2²⁶ = 621796207 is a prime.

It is a Sophie Germain prime.

Together with 688905073, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (688905073) 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, 344452535 + 344452536.

It is an arithmetic number, because the mean of its divisors is an integer number (344452536).

Almost surely, 2^688905071 is an apocalyptic number.

688905071 is a deficient number, since it is larger than the sum of its proper divisors (1).

688905071 is an equidigital number, since it uses as much as digits as its factorization.

688905071 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 120960, while the sum is 44.

The square root of 688905071 is about 26247.0011810873. The cubic root of 688905071 is about 883.1879340920.

The spelling of 688905071 in words is "six hundred eighty-eight million, nine hundred five thousand, seventy-one".