21403233220 has 12 divisors (see below), whose sum is σ = 44946789804. Its totient is φ = 8561293280.

The previous prime is 21403233209. The next prime is 21403233251. The reversal of 21403233220 is 2233230412.

It can be written as a sum of positive squares in 2 ways, for example, as 6031696896 + 15371536324 = 77664^2 + 123982^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21403233191 and 21403233200.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 535080811 + ... + 535080850.

It is an arithmetic number, because the mean of its divisors is an integer number (3745565817).

Almost surely, 2^21403233220 is an apocalyptic number.

21403233220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21403233220 is an abundant number, since it is smaller than the sum of its proper divisors (23543556584).

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

21403233220 is a wasteful number, since it uses less digits than its factorization.

21403233220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1070161670 (or 1070161668 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 22.

Adding to 21403233220 its reverse (2233230412), we get a palindrome (23636463632).

The spelling of 21403233220 in words is "twenty-one billion, four hundred three million, two hundred thirty-three thousand, two hundred twenty".