212211212220 has 144 divisors (see below), whose sum is σ = 735866389440. Its totient is φ = 48492177408.

The previous prime is 212211212207. The next prime is 212211212243. The reversal of 212211212220 is 22212112212.

It is a happy number.

212211212220 is a `hidden beast` number, since 21 + 2 + 211 + 212 + 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 = 212211212193 and 212211212202.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5035396 + ... + 5077364.

It is an arithmetic number, because the mean of its divisors is an integer number (5110183260).

Almost surely, 2^212211212220 is an apocalyptic number.

212211212220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 212211212220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (367933194720).

212211212220 is an abundant number, since it is smaller than the sum of its proper divisors (523655177220).

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

212211212220 is a wasteful number, since it uses less digits than its factorization.

212211212220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46004 (or 45999 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 212211212220 its reverse (22212112212), we get a palindrome (234423324432).

The spelling of 212211212220 in words is "two hundred twelve billion, two hundred eleven million, two hundred twelve thousand, two hundred twenty".