It is a plaindrome in base 10.
It is a congruent number.
It is an unprimeable number.
Almost surely, 2123456788 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 123456788, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (143265024).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
123456788 is a wasteful number, since it uses less digits than its factorization.
123456788 is an odious number, because the sum of its binary digits is odd.
The square root of 123456788 is about 11111.1110155556. Note that the first 3 decimals coincide. The cubic root of 123456788 is about 497.9338578738.
The spelling of 123456788 in words is "one hundred twenty-three million, four hundred fifty-six thousand, seven hundred eighty-eight".