21243188250 has 128 divisors (see below), whose sum is σ = 59028652800. Its totient is φ = 5653872000.

The previous prime is 21243188249. The next prime is 21243188293. The reversal of 21243188250 is 5288134212.

It is a happy number.

21243188250 is a `hidden beast` number, since 212 + 4 + 318 + 82 + 50 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3837985 + ... + 3843515.

It is an arithmetic number, because the mean of its divisors is an integer number (461161350).

Almost surely, 2^21243188250 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21243188250, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29514326400).

21243188250 is an abundant number, since it is smaller than the sum of its proper divisors (37785464550).

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

21243188250 is a wasteful number, since it uses less digits than its factorization.

21243188250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6126 (or 6110 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

The spelling of 21243188250 in words is "twenty-one billion, two hundred forty-three million, one hundred eighty-eight thousand, two hundred fifty".