11223121220 has 24 divisors (see below), whose sum is σ = 24381264600. Its totient is φ = 4334446592.

The previous prime is 11223121201. The next prime is 11223121253. The reversal of 11223121220 is 2212132211.

It can be written as a sum of positive squares in 4 ways, for example, as 310393924 + 10912727296 = 17618^2 + 104464^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9674525 + ... + 9675684.

It is an arithmetic number, because the mean of its divisors is an integer number (1015886025).

Almost surely, 2^11223121220 is an apocalyptic number.

11223121220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11223121220 is an abundant number, since it is smaller than the sum of its proper divisors (13158143380).

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

11223121220 is a wasteful number, since it uses less digits than its factorization.

11223121220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19350247 (or 19350245 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 11223121220 its reverse (2212132211), we get a palindrome (13435253431).

The spelling of 11223121220 in words is "eleven billion, two hundred twenty-three million, one hundred twenty-one thousand, two hundred twenty".