205402221 has 6 divisors (see below), whose sum is σ = 296692110. Its totient is φ = 136934808.

The previous prime is 205402199. The next prime is 205402243. The reversal of 205402221 is 122204502.

205402221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (205402199) and next prime (205402243).

It can be written as a sum of positive squares in only one way, i.e., 140422500 + 64979721 = 11850^2 + 8061^2 .

It is not a de Polignac number, because 205402221 - 2⁹ = 205401709 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 205402194 and 205402203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205402261) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11411226 + ... + 11411243.

It is an arithmetic number, because the mean of its divisors is an integer number (49448685).

Almost surely, 2^205402221 is an apocalyptic number.

It is an amenable number.

205402221 is a deficient number, since it is larger than the sum of its proper divisors (91289889).

205402221 is a wasteful number, since it uses less digits than its factorization.

205402221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22822475 (or 22822472 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 205402221 is about 14331.8603467938. The cubic root of 205402221 is about 590.0222351095.

Adding to 205402221 its reverse (122204502), we get a palindrome (327606723).

The spelling of 205402221 in words is "two hundred five million, four hundred two thousand, two hundred twenty-one".