21250244052 has 288 divisors, whose sum is σ = 61024803840. Its totient is φ = 6440394240.

The previous prime is 21250244051. The next prime is 21250244063. The reversal of 21250244052 is 25044205212.

21250244052 is a `hidden beast` number, since 2 + 1 + 250 + 2 + 4 + 405 + 2 = 666.

It is a super-2 number, since 2×21250244052² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21250244051) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 69218883 + ... + 69219189.

It is an arithmetic number, because the mean of its divisors is an integer number (211891680).

Almost surely, 2^21250244052 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 21250244052, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30512401920).

21250244052 is an abundant number, since it is smaller than the sum of its proper divisors (39774559788).

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

21250244052 is a wasteful number, since it uses less digits than its factorization.

21250244052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 473 (or 459 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 27.

Adding to 21250244052 its reverse (25044205212), we get a palindrome (46294449264).

The spelling of 21250244052 in words is "twenty-one billion, two hundred fifty million, two hundred forty-four thousand, fifty-two".