21245620224 has 208 divisors, whose sum is σ = 58984636032. Its totient is φ = 6795362304.

The previous prime is 21245620183. The next prime is 21245620247. The reversal of 21245620224 is 42202654212.

It is a junction number, because it is equal to n+sod(n) for n = 21245620191 and 21245620200.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 37736167 + ... + 37736729.

Almost surely, 2^21245620224 is an apocalyptic number.

21245620224 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 21245620224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29492318016).

21245620224 is an abundant number, since it is smaller than the sum of its proper divisors (37739015808).

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

21245620224 is an equidigital number, since it uses as much as digits as its factorization.

21245620224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 710 (or 688 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 30.

The spelling of 21245620224 in words is "twenty-one billion, two hundred forty-five million, six hundred twenty thousand, two hundred twenty-four".