211100211221220 has 72 divisors (see below), whose sum is σ = 640339211139264. Its totient is φ = 56293222294848.

The previous prime is 211100211221213. The next prime is 211100211221267. The reversal of 211100211221220 is 22122112001112.

211100211221220 is a `hidden beast` number, since 2 + 1 + 1 + 10 + 0 + 211 + 221 + 220 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 211100211221193 and 211100211221202.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 66331657 + ... + 69441263.

It is an arithmetic number, because the mean of its divisors is an integer number (8893600154712).

Almost surely, 2^{211100211221220} is an apocalyptic number.

211100211221220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

211100211221220 is an abundant number, since it is smaller than the sum of its proper divisors (429238999918044).

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

211100211221220 is a wasteful number, since it uses less digits than its factorization.

211100211221220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3486769 (or 3486764 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 211100211221220 its reverse (22122112001112), we get a palindrome (233222323222332).

The spelling of 211100211221220 in words is "two hundred eleven trillion, one hundred billion, two hundred eleven million, two hundred twenty-one thousand, two hundred twenty".