221344020 has 36 divisors (see below), whose sum is σ = 671410740. Its totient is φ = 59025024.

The previous prime is 221344007. The next prime is 221344031. The reversal of 221344020 is 20443122.

221344020 is a `hidden beast` number, since 221 + 3 + 440 + 2 + 0 = 666.

221344020 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 169676676 + 51667344 = 13026^2 + 7188^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 221343984 and 221344002.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 614665 + ... + 615024.

Almost surely, 2^221344020 is an apocalyptic number.

221344020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221344020 is an abundant number, since it is smaller than the sum of its proper divisors (450066720).

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

221344020 is a wasteful number, since it uses less digits than its factorization.

221344020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1229704 (or 1229699 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 221344020 is about 14877.6348926837. The cubic root of 221344020 is about 604.9079112164.

Adding to 221344020 its reverse (20443122), we get a palindrome (241787142).

The spelling of 221344020 in words is "two hundred twenty-one million, three hundred forty-four thousand, twenty".