221055421 has 8 divisors (see below), whose sum is σ = 226537560. Its totient is φ = 215621952.

The previous prime is 221055409. The next prime is 221055431. The reversal of 221055421 is 124550122.

It can be written as a sum of positive squares in 4 ways, for example, as 116402521 + 104652900 = 10789^2 + 10230^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 221055421 - 2⁷ = 221055293 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221055392 and 221055401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221055431) 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, 2886 + ... + 21223.

It is an arithmetic number, because the mean of its divisors is an integer number (28317195).

Almost surely, 2^221055421 is an apocalyptic number.

It is an amenable number.

221055421 is a deficient number, since it is larger than the sum of its proper divisors (5482139).

221055421 is a wasteful number, since it uses less digits than its factorization.

221055421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24335.

The product of its (nonzero) digits is 800, while the sum is 22.

The square root of 221055421 is about 14867.9326404178. The cubic root of 221055421 is about 604.6448941766.

The spelling of 221055421 in words is "two hundred twenty-one million, fifty-five thousand, four hundred twenty-one".