689256638 has 12 divisors (see below), whose sum is σ = 1202682672. Its totient is φ = 295395660.

The previous prime is 689256637. The next prime is 689256643. The reversal of 689256638 is 836652986.

689256638 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 689256638.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (689256637) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3516518 + ... + 3516713.

It is an arithmetic number, because the mean of its divisors is an integer number (100223556).

Almost surely, 2^689256638 is an apocalyptic number.

689256638 is a deficient number, since it is larger than the sum of its proper divisors (513426034).

689256638 is a wasteful number, since it uses less digits than its factorization.

689256638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7033247 (or 7033240 counting only the distinct ones).

The product of its digits is 3732480, while the sum is 53.

The square root of 689256638 is about 26253.6976062421. The cubic root of 689256638 is about 883.3381468192.

The spelling of 689256638 in words is "six hundred eighty-nine million, two hundred fifty-six thousand, six hundred thirty-eight".