211121220 has 24 divisors (see below), whose sum is σ = 591139584. Its totient is φ = 56298976.

The previous prime is 211121213. The next prime is 211121237. The reversal of 211121220 is 22121112.

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 = 211121196 and 211121205.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1759284 + ... + 1759403.

It is an arithmetic number, because the mean of its divisors is an integer number (24630816).

Almost surely, 2^211121220 is an apocalyptic number.

211121220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

211121220 is an abundant number, since it is smaller than the sum of its proper divisors (380018364).

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

211121220 is a wasteful number, since it uses less digits than its factorization.

211121220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3518699 (or 3518697 counting only the distinct ones).

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

The square root of 211121220 is about 14530.0110116958. The cubic root of 211121220 is about 595.4481664544.

Adding to 211121220 its reverse (22121112), we get a palindrome (233242332).

The spelling of 211121220 in words is "two hundred eleven million, one hundred twenty-one thousand, two hundred twenty".