689138955969408 has 512 divisors, whose sum is σ = 2338267127040000. Its totient is φ = 195730498732032.

The previous prime is 689138955969361. The next prime is 689138955969427. The reversal of 689138955969408 is 804969559831986.

689138955969408 is a `hidden beast` number, since 6 + 8 + 9 + 1 + 3 + 8 + 9 + 5 + 596 + 9 + 4 + 0 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 5377406260 + ... + 5377534412.

It is an arithmetic number, because the mean of its divisors is an integer number (4566927982500).

Almost surely, 2^{689138955969408} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 689138955969408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1169133563520000).

689138955969408 is an abundant number, since it is smaller than the sum of its proper divisors (1649128171070592).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

689138955969408 is a wasteful number, since it uses less digits than its factorization.

689138955969408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129499 (or 129481 counting only the distinct ones).

The product of its (nonzero) digits is 36279705600, while the sum is 90.

The spelling of 689138955969408 in words is "six hundred eighty-nine trillion, one hundred thirty-eight billion, nine hundred fifty-five million, nine hundred sixty-nine thousand, four hundred eight".