211100021220 has 96 divisors (see below), whose sum is σ = 651199118976. Its totient is φ = 50669056000.

The previous prime is 211100021213. The next prime is 211100021261. The reversal of 211100021220 is 22120001112.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 211100021196 and 211100021205.

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 31 ways as a sum of consecutive naturals, for example, 1516749 + ... + 1650068.

It is an arithmetic number, because the mean of its divisors is an integer number (6783324156).

Almost surely, 2^211100021220 is an apocalyptic number.

211100021220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

211100021220 is an abundant number, since it is smaller than the sum of its proper divisors (440099097756).

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

211100021220 is a wasteful number, since it uses less digits than its factorization.

211100021220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3166941 (or 3166939 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 211100021220 its reverse (22120001112), we get a palindrome (233220022332).

The spelling of 211100021220 in words is "two hundred eleven billion, one hundred million, twenty-one thousand, two hundred twenty".