21253224500424 has 192 divisors, whose sum is σ = 65986662268800. Its totient is φ = 6053630349312.

The previous prime is 21253224500359. The next prime is 21253224500467. The reversal of 21253224500424 is 42400542235212.

21253224500424 is a `hidden beast` number, since 2 + 1 + 2 + 5 + 3 + 224 + 5 + 0 + 0 + 424 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

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, 1209691512 + ... + 1209709080.

It is an arithmetic number, because the mean of its divisors is an integer number (343680532650).

Almost surely, 2^{21253224500424} is an apocalyptic number.

21253224500424 is a gapful number since it is divisible by the number (24) 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 21253224500424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32993331134400).

21253224500424 is an abundant number, since it is smaller than the sum of its proper divisors (44733437768376).

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

21253224500424 is a wasteful number, since it uses less digits than its factorization.

21253224500424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24852 (or 24845 counting only the distinct ones).

The product of its (nonzero) digits is 153600, while the sum is 36.

Adding to 21253224500424 its reverse (42400542235212), we get a palindrome (63653766735636).

The spelling of 21253224500424 in words is "twenty-one trillion, two hundred fifty-three billion, two hundred twenty-four million, five hundred thousand, four hundred twenty-four".