221334021 has 12 divisors (see below), whose sum is σ = 336531520. Its totient is φ = 139789800.

The previous prime is 221334013. The next prime is 221334023. The reversal of 221334021 is 120433122.

It is not a de Polignac number, because 221334021 - 2³ = 221334013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221333985 and 221334003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221334023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 647005 + ... + 647346.

Almost surely, 2^221334021 is an apocalyptic number.

It is an amenable number.

221334021 is a deficient number, since it is larger than the sum of its proper divisors (115197499).

221334021 is a wasteful number, since it uses less digits than its factorization.

221334021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1294376 (or 1294373 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 221334021 is about 14877.2988475731. The cubic root of 221334021 is about 604.8988023711.

Adding to 221334021 its reverse (120433122), we get a palindrome (341767143).

The spelling of 221334021 in words is "two hundred twenty-one million, three hundred thirty-four thousand, twenty-one".