21121223320 has 32 divisors (see below), whose sum is σ = 48627936720. Its totient is φ = 8252012160.

The previous prime is 21121223293. The next prime is 21121223443. The reversal of 21121223320 is 2332212112.

It is a super-2 number, since 2×21121223320² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6138171 + ... + 6141610.

Almost surely, 2^21121223320 is an apocalyptic number.

21121223320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21121223320 is an abundant number, since it is smaller than the sum of its proper divisors (27506713400).

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

21121223320 is a wasteful number, since it uses less digits than its factorization.

21121223320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12279835 (or 12279831 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 21121223320 its reverse (2332212112), we get a palindrome (23453435432).

The spelling of 21121223320 in words is "twenty-one billion, one hundred twenty-one million, two hundred twenty-three thousand, three hundred twenty".