221331020 has 24 divisors (see below), whose sum is σ = 465633168. Its totient is φ = 88372800.

The previous prime is 221331013. The next prime is 221331029. The reversal of 221331020 is 20133122.

It is a happy number.

221331020 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 221330986 and 221331004.

It is not an unprimeable number, because it can be changed into a prime (221331029) 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, 1730 + ... + 21110.

It is an arithmetic number, because the mean of its divisors is an integer number (19401382).

Almost surely, 2^221331020 is an apocalyptic number.

221331020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221331020 is an abundant number, since it is smaller than the sum of its proper divisors (244302148).

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

221331020 is a wasteful number, since it uses less digits than its factorization.

221331020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19961 (or 19959 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 221331020 is about 14877.1979888687. The cubic root of 221331020 is about 604.8960684798.

Adding to 221331020 its reverse (20133122), we get a palindrome (241464142).

It can be divided in two parts, 2213 and 31020, that added together give a palindrome (33233).

The spelling of 221331020 in words is "two hundred twenty-one million, three hundred thirty-one thousand, twenty".