11211211220 has 24 divisors (see below), whose sum is σ = 25683866208. Its totient is φ = 4076804000.

The previous prime is 11211211217. The next prime is 11211211229. The reversal of 11211211220 is 2211211211.

It is a junction number, because it is equal to n+sod(n) for n = 11211211195 and 11211211204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11211211229) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25479806 + ... + 25480245.

It is an arithmetic number, because the mean of its divisors is an integer number (1070161092).

Almost surely, 2^11211211220 is an apocalyptic number.

11211211220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11211211220 is an abundant number, since it is smaller than the sum of its proper divisors (14472654988).

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

11211211220 is a wasteful number, since it uses less digits than its factorization.

11211211220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50960071 (or 50960069 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 11211211220 its reverse (2211211211), we get a palindrome (13422422431).

Subtracting from 11211211220 its reverse (2211211211), we obtain a palindrome (9000000009).

The spelling of 11211211220 in words is "eleven billion, two hundred eleven million, two hundred eleven thousand, two hundred twenty".