221400221 has 8 divisors (see below), whose sum is σ = 258412800. Its totient is φ = 185733648.

The previous prime is 221400211. The next prime is 221400229. The reversal of 221400221 is 122004122.

221400221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 221400221 - 2²² = 217205917 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 221400196 and 221400205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221400229) 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, 336146 + ... + 336803.

It is an arithmetic number, because the mean of its divisors is an integer number (32301600).

Almost surely, 2^221400221 is an apocalyptic number.

It is an amenable number.

221400221 is a deficient number, since it is larger than the sum of its proper divisors (37012579).

221400221 is an equidigital number, since it uses as much as digits as its factorization.

221400221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 673003.

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

The square root of 221400221 is about 14879.5235474796. The cubic root of 221400221 is about 604.9591038540.

Adding to 221400221 its reverse (122004122), we get a palindrome (343404343).

The spelling of 221400221 in words is "two hundred twenty-one million, four hundred thousand, two hundred twenty-one".