21001203320 has 16 divisors (see below), whose sum is σ = 47252707560. Its totient is φ = 8400481312.

The previous prime is 21001203313. The next prime is 21001203323. The reversal of 21001203320 is 2330210012.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21001203295 and 21001203304.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001203323) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 262515002 + ... + 262515081.

Almost surely, 2^21001203320 is an apocalyptic number.

21001203320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21001203320 is an abundant number, since it is smaller than the sum of its proper divisors (26251504240).

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

21001203320 is a wasteful number, since it uses less digits than its factorization.

21001203320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 525030094 (or 525030090 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 14.

Adding to 21001203320 its reverse (2330210012), we get a palindrome (23331413332).

The spelling of 21001203320 in words is "twenty-one billion, one million, two hundred three thousand, three hundred twenty".