11221232220 has 144 divisors (see below), whose sum is σ = 37461426912. Its totient is φ = 2696171520.

The previous prime is 11221232147. The next prime is 11221232257. The reversal of 11221232220 is 2223212211.

11221232220 is a `hidden beast` number, since 112 + 212 + 322 + 20 = 666.

It is a super-2 number, since 2×11221232220² (a number of 21 digits) contains 22 as substring.

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 = 11221232193 and 11221232202.

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, 198664 + ... + 248816.

It is an arithmetic number, because the mean of its divisors is an integer number (260148798).

Almost surely, 2^11221232220 is an apocalyptic number.

11221232220 is a gapful number since it is divisible by the number (10) 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 11221232220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18730713456).

11221232220 is an abundant number, since it is smaller than the sum of its proper divisors (26240194692).

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

11221232220 is a wasteful number, since it uses less digits than its factorization.

11221232220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50292 (or 50287 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 11221232220 its reverse (2223212211), we get a palindrome (13444444431).

The spelling of 11221232220 in words is "eleven billion, two hundred twenty-one million, two hundred thirty-two thousand, two hundred twenty".