2121211220220 has 72 divisors (see below), whose sum is σ = 6434998852464. Its totient is φ = 565598466048.

The previous prime is 2121211220213. The next prime is 2121211220221. The reversal of 2121211220220 is 220221121212.

It is a happy number.

2121211220220 is a `hidden beast` number, since 2 + 1 + 212 + 11 + 220 + 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 = 2121211220193 and 2121211220202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121211220221) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1176487 + ... + 2372033.

It is an arithmetic number, because the mean of its divisors is an integer number (89374984062).

Almost surely, 2^{2121211220220} is an apocalyptic number.

2121211220220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2121211220220 is an abundant number, since it is smaller than the sum of its proper divisors (4313787632244).

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

2121211220220 is a wasteful number, since it uses less digits than its factorization.

2121211220220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1205419 (or 1205414 counting only the distinct ones).

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

Adding to 2121211220220 its reverse (220221121212), we get a palindrome (2341432341432).

It can be divided in two parts, 212121 and 1220220, that added together give a palindrome (1432341).

The spelling of 2121211220220 in words is "two trillion, one hundred twenty-one billion, two hundred eleven million, two hundred twenty thousand, two hundred twenty".