28111724550 has 288 divisors, whose sum is σ = 97851237120. Its totient is φ = 5618937600.

The previous prime is 28111724549. The next prime is 28111724573. The reversal of 28111724550 is 5542711182.

It is a happy number.

28111724550 is a `hidden beast` number, since 2 + 81 + 1 + 1 + 7 + 24 + 550 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 759985 + ... + 796115.

It is an arithmetic number, because the mean of its divisors is an integer number (339761240).

Almost surely, 2^28111724550 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28111724550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48925618560).

28111724550 is an abundant number, since it is smaller than the sum of its proper divisors (69739512570).

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

28111724550 is a wasteful number, since it uses less digits than its factorization.

28111724550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36188 (or 36180 counting only the distinct ones).

The product of its (nonzero) digits is 22400, while the sum is 36.

The spelling of 28111724550 in words is "twenty-eight billion, one hundred eleven million, seven hundred twenty-four thousand, five hundred fifty".