221120420 has 24 divisors (see below), whose sum is σ = 464667000. Its totient is φ = 88388352.

The previous prime is 221120407. The next prime is 221120429. The reversal of 221120420 is 24021122.

It can be written as a sum of positive squares in 4 ways, for example, as 40271716 + 180848704 = 6346^2 + 13448^2 .

It is a junction number, because it is equal to n+sod(n) for n = 221120395 and 221120404.

It is not an unprimeable number, because it can be changed into a prime (221120429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37856 + ... + 43304.

It is an arithmetic number, because the mean of its divisors is an integer number (19361125).

Almost surely, 2^221120420 is an apocalyptic number.

221120420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221120420 is an abundant number, since it is smaller than the sum of its proper divisors (243546580).

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

221120420 is a wasteful number, since it uses less digits than its factorization.

221120420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7487 (or 7485 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 221120420 is about 14870.1183586413. The cubic root of 221120420 is about 604.7041515066.

Adding to 221120420 its reverse (24021122), we get a palindrome (245141542).

The spelling of 221120420 in words is "two hundred twenty-one million, one hundred twenty thousand, four hundred twenty".