210021211220 has 24 divisors (see below), whose sum is σ = 441213184104. Its totient is φ = 83976362496.

The previous prime is 210021211219. The next prime is 210021211241. The reversal of 210021211220 is 22112120012.

210021211220 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 73437748036 + 136583463184 = 270994^2 + 369572^2 .

It is a junction number, because it is equal to n+sod(n) for n = 210021211195 and 210021211204.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 1953977 + ... + 2058656.

It is an arithmetic number, because the mean of its divisors is an integer number (18383882671).

Almost surely, 2^210021211220 is an apocalyptic number.

210021211220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

210021211220 is an abundant number, since it is smaller than the sum of its proper divisors (231191972884).

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

210021211220 is a wasteful number, since it uses less digits than its factorization.

210021211220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4015259 (or 4015257 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 210021211220 its reverse (22112120012), we get a palindrome (232133331232).

The spelling of 210021211220 in words is "two hundred ten billion, twenty-one million, two hundred eleven thousand, two hundred twenty".