11211211220220 has 144 divisors (see below), whose sum is σ = 37100551269600. Its totient is φ = 2717749670400.

The previous prime is 11211211220213. The next prime is 11211211220221. The reversal of 11211211220220 is 2202211211211.

11211211220220 is a `hidden beast` number, since 1 + 1 + 2 + 11 + 211 + 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 = 11211211220193 and 11211211220202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11211211220221) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 49904706 + ... + 50128854.

It is an arithmetic number, because the mean of its divisors is an integer number (257642717150).

Almost surely, 2^{11211211220220} is an apocalyptic number.

11211211220220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11211211220220 is an abundant number, since it is smaller than the sum of its proper divisors (25889340049380).

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

11211211220220 is a wasteful number, since it uses less digits than its factorization.

11211211220220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249436 (or 249431 counting only the distinct ones).

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

Adding to 11211211220220 its reverse (2202211211211), we get a palindrome (13413422431431).

Subtracting from 11211211220220 its reverse (2202211211211), we obtain a palindrome (9009000009009).

The spelling of 11211211220220 in words is "eleven trillion, two hundred eleven billion, two hundred eleven million, two hundred twenty thousand, two hundred twenty".