21244203020 has 48 divisors (see below), whose sum is σ = 44841535200. Its totient is φ = 8454190080.

The previous prime is 21244202963. The next prime is 21244203037. The reversal of 21244203020 is 2030244212.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 21244202983 and 21244203001.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8236091 + ... + 8238669.

It is an arithmetic number, because the mean of its divisors is an integer number (934198650).

Almost surely, 2^21244203020 is an apocalyptic number.

21244203020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21244203020 is an abundant number, since it is smaller than the sum of its proper divisors (23597332180).

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

21244203020 is a wasteful number, since it uses less digits than its factorization.

21244203020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4538 (or 4536 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

Adding to 21244203020 its reverse (2030244212), we get a palindrome (23274447232).

The spelling of 21244203020 in words is "twenty-one billion, two hundred forty-four million, two hundred three thousand, twenty".