12211220 has 24 divisors (see below), whose sum is σ = 29307264. Its totient is φ = 4186656.

The previous prime is 12211217. The next prime is 12211223. The reversal of 12211220 is 2211221.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (12211217) and next prime (12211223).

It is a super-2 number, since 2×12211220² = 298227787776800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12211223) 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, 43472 + ... + 43751.

It is an arithmetic number, because the mean of its divisors is an integer number (1221136).

Almost surely, 2^12211220 is an apocalyptic number.

12211220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12211220 is an abundant number, since it is smaller than the sum of its proper divisors (17096044).

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

12211220 is a wasteful number, since it uses less digits than its factorization.

12211220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87239 (or 87237 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 12211220 is about 3494.4556085319. The cubic root of 12211220 is about 230.2783020576.

Adding to 12211220 its reverse (2211221), we get a palindrome (14422441).

Subtracting from 12211220 its reverse (2211221), we obtain a palindrome (9999999).

The spelling of 12211220 in words is "twelve million, two hundred eleven thousand, two hundred twenty".