221211120 has 80 divisors (see below), whose sum is σ = 738515232. Its totient is φ = 54451200.

The previous prime is 221211083. The next prime is 221211127. The reversal of 221211120 is 21112122.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×221211120² = 97868719223308800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 221211096 and 221211105.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221211127) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32331 + ... + 38570.

Almost surely, 2^221211120 is an apocalyptic number.

221211120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221211120 is an abundant number, since it is smaller than the sum of its proper divisors (517304112).

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

221211120 is a wasteful number, since it uses less digits than its factorization.

221211120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70930 (or 70924 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

The square root of 221211120 is about 14873.1677863191. The cubic root of 221211120 is about 604.7868201405.

Adding to 221211120 its reverse (21112122), we get a palindrome (242323242).

The spelling of 221211120 in words is "two hundred twenty-one million, two hundred eleven thousand, one hundred twenty".