211121111220 has 48 divisors (see below), whose sum is σ = 591162307008. Its totient is φ = 56296753920.

The previous prime is 211121111219. The next prime is 211121111231. The reversal of 211121111220 is 22111121112.

It is a happy number.

211121111220 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 211121111220.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1971087 + ... + 2075433.

It is an arithmetic number, because the mean of its divisors is an integer number (12315881396).

Almost surely, 2^211121111220 is an apocalyptic number.

211121111220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

211121111220 is an abundant number, since it is smaller than the sum of its proper divisors (380041195788).

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

211121111220 is a wasteful number, since it uses less digits than its factorization.

211121111220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138080 (or 138078 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 211121111220 its reverse (22111121112), we get a palindrome (233232232332).

The spelling of 211121111220 in words is "two hundred eleven billion, one hundred twenty-one million, one hundred eleven thousand, two hundred twenty".