21140233220 has 24 divisors (see below), whose sum is σ = 44397288600. Its totient is φ = 8455560192.

The previous prime is 21140233201. The next prime is 21140233229. The reversal of 21140233220 is 2233204112.

It can be written as a sum of positive squares in 4 ways, for example, as 330439684 + 20809793536 = 18178^2 + 144256^2 .

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 = 21140233192 and 21140233201.

It is not an unprimeable number, because it can be changed into a prime (21140233229) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 500276 + ... + 540884.

It is an arithmetic number, because the mean of its divisors is an integer number (1849887025).

Almost surely, 2^21140233220 is an apocalyptic number.

21140233220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21140233220 is an abundant number, since it is smaller than the sum of its proper divisors (23257055380).

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

21140233220 is a wasteful number, since it uses less digits than its factorization.

21140233220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66647 (or 66645 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 21140233220 its reverse (2233204112), we get a palindrome (23373437332).

The spelling of 21140233220 in words is "twenty-one billion, one hundred forty million, two hundred thirty-three thousand, two hundred twenty".