221215120 has 40 divisors (see below), whose sum is σ = 587801664. Its totient is φ = 75844992.

The previous prime is 221215073. The next prime is 221215129. The reversal of 221215120 is 21512122.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×221215120² = 97872258633228800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 221215094 and 221215103.

It is not an unprimeable number, because it can be changed into a prime (221215129) 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, 196954 + ... + 198073.

Almost surely, 2^221215120 is an apocalyptic number.

221215120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221215120 is an abundant number, since it is smaller than the sum of its proper divisors (366586544).

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

221215120 is a wasteful number, since it uses less digits than its factorization.

221215120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 395047 (or 395041 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 221215120 is about 14873.3022560560. The cubic root of 221215120 is about 604.7904654255.

Adding to 221215120 its reverse (21512122), we get a palindrome (242727242).

The spelling of 221215120 in words is "two hundred twenty-one million, two hundred fifteen thousand, one hundred twenty".