123735728550 has 144 divisors (see below), whose sum is σ = 357602236992. Its totient is φ = 28231963200.

The previous prime is 123735728531. The next prime is 123735728591. The reversal of 123735728550 is 55827537321.

It is a self number, because there is not a number n which added to its sum of digits gives 123735728550.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 4182109 + ... + 4211591.

It is an arithmetic number, because the mean of its divisors is an integer number (2483348868).

Almost surely, 2^123735728550 is an apocalyptic number.

123735728550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 123735728550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (178801118496).

123735728550 is an abundant number, since it is smaller than the sum of its proper divisors (233866508442).

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

123735728550 is a wasteful number, since it uses less digits than its factorization.

123735728550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30083 (or 30071 counting only the distinct ones).

The product of its (nonzero) digits is 1764000, while the sum is 48.

The spelling of 123735728550 in words is "one hundred twenty-three billion, seven hundred thirty-five million, seven hundred twenty-eight thousand, five hundred fifty".