123456778920 has 192 divisors, whose sum is σ = 419794876800. Its totient is φ = 31406538240.

The previous prime is 123456778901. The next prime is 123456778981. The reversal of 123456778920 is 29877654321.

It is a happy number.

123456778920 is a `hidden beast` number, since 1 + 2 + 3 + 4 + 567 + 78 + 9 + 2 + 0 = 666.

123456778920 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×123456778920² (a number of 23 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (54) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3118450 + ... + 3157790.

It is an arithmetic number, because the mean of its divisors is an integer number (2186431650).

It is a 2-persistent number, because it is pandigital, and so is 2⋅123456778920 = 246913557840, but 3⋅123456778920 = 370370336760 is not.

Almost surely, 2^123456778920 is an apocalyptic number.

123456778920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 123456778920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (209897438400).

123456778920 is an abundant number, since it is smaller than the sum of its proper divisors (296338097880).

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

123456778920 is a wasteful number, since it uses less digits than its factorization.

123456778920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39760 (or 39753 counting only the distinct ones).

The product of its (nonzero) digits is 5080320, while the sum is 54.

The spelling of 123456778920 in words is "one hundred twenty-three billion, four hundred fifty-six million, seven hundred seventy-eight thousand, nine hundred twenty".