21131214220 has 12 divisors (see below), whose sum is σ = 44375549904. Its totient is φ = 8452485680.

The previous prime is 21131214199. The next prime is 21131214227. The reversal of 21131214220 is 2241213112.

It is not an unprimeable number, because it can be changed into a prime (21131214227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 528280336 + ... + 528280375.

It is an arithmetic number, because the mean of its divisors is an integer number (3697962492).

Almost surely, 2^21131214220 is an apocalyptic number.

21131214220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21131214220 is an abundant number, since it is smaller than the sum of its proper divisors (23244335684).

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

21131214220 is a wasteful number, since it uses less digits than its factorization.

21131214220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1056560720 (or 1056560718 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 21131214220 its reverse (2241213112), we get a palindrome (23372427332).

The spelling of 21131214220 in words is "twenty-one billion, one hundred thirty-one million, two hundred fourteen thousand, two hundred twenty".