21001302220 has 24 divisors (see below), whose sum is σ = 44107875504. Its totient is φ = 8399541696.

The previous prime is 21001302193. The next prime is 21001302221. The reversal of 21001302220 is 2220310012.

It is a self number, because there is not a number n which added to its sum of digits gives 21001302220.

It is not an unprimeable number, because it can be changed into a prime (21001302221) by changing a digit.

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, 129102 + ... + 242218.

It is an arithmetic number, because the mean of its divisors is an integer number (1837828146).

Almost surely, 2^21001302220 is an apocalyptic number.

21001302220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21001302220 is an abundant number, since it is smaller than the sum of its proper divisors (23106573284).

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

21001302220 is a wasteful number, since it uses less digits than its factorization.

21001302220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122409 (or 122407 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

Adding to 21001302220 its reverse (2220310012), we get a palindrome (23221612232).

The spelling of 21001302220 in words is "twenty-one billion, one million, three hundred two thousand, two hundred twenty".