688639607 has 2 divisors, whose sum is σ = 688639608. Its totient is φ = 688639606.

The previous prime is 688639583. The next prime is 688639639. The reversal of 688639607 is 706936886.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 688639607 - 2⁸ = 688639351 is a prime.

It is a super-2 number, since 2×688639607² = 948449016658228898, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (688639657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344319803 + 344319804.

It is an arithmetic number, because the mean of its divisors is an integer number (344319804).

Almost surely, 2^688639607 is an apocalyptic number.

688639607 is a deficient number, since it is larger than the sum of its proper divisors (1).

688639607 is an equidigital number, since it uses as much as digits as its factorization.

688639607 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2612736, while the sum is 53.

The square root of 688639607 is about 26241.9436589594. The cubic root of 688639607 is about 883.0744764072.

The spelling of 688639607 in words is "six hundred eighty-eight million, six hundred thirty-nine thousand, six hundred seven".