21331201220 has 48 divisors (see below), whose sum is σ = 51226226688. Its totient is φ = 7309077120.

The previous prime is 21331201217. The next prime is 21331201273. The reversal of 21331201220 is 2210213312.

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 15 ways as a sum of consecutive naturals, for example, 187010 + ... + 278630.

It is an arithmetic number, because the mean of its divisors is an integer number (1067213056).

Almost surely, 2^21331201220 is an apocalyptic number.

21331201220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21331201220 is an abundant number, since it is smaller than the sum of its proper divisors (29895025468).

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

21331201220 is a wasteful number, since it uses less digits than its factorization.

21331201220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93300 (or 93298 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 21331201220 its reverse (2210213312), we get a palindrome (23541414532).

The spelling of 21331201220 in words is "twenty-one billion, three hundred thirty-one million, two hundred one thousand, two hundred twenty".