688874639 has 2 divisors, whose sum is σ = 688874640. Its totient is φ = 688874638.

The previous prime is 688874617. The next prime is 688874701. The reversal of 688874639 is 936478886.

688874639 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 688874639 - 2¹² = 688870543 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (688874339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344437319 + 344437320.

It is an arithmetic number, because the mean of its divisors is an integer number (344437320).

Almost surely, 2^688874639 is an apocalyptic number.

688874639 is a deficient number, since it is larger than the sum of its proper divisors (1).

688874639 is an equidigital number, since it uses as much as digits as its factorization.

688874639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13934592, while the sum is 59.

The square root of 688874639 is about 26246.4214513141. The cubic root of 688874639 is about 883.1749291212.

The spelling of 688874639 in words is "six hundred eighty-eight million, eight hundred seventy-four thousand, six hundred thirty-nine".