205435021 has 16 divisors (see below), whose sum is σ = 240651648. Its totient is φ = 173286400.

The previous prime is 205435001. The next prime is 205435099. The reversal of 205435021 is 120534502.

205435021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 205435021 - 2¹⁹ = 204910733 is a prime.

It is a super-3 number, since 3×205435021³ (a number of 26 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 205434983 and 205435001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205435001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5541 + ... + 21013.

It is an arithmetic number, because the mean of its divisors is an integer number (15040728).

Almost surely, 2^205435021 is an apocalyptic number.

It is an amenable number.

205435021 is a deficient number, since it is larger than the sum of its proper divisors (35216627).

205435021 is a wasteful number, since it uses less digits than its factorization.

205435021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15572.

The product of its (nonzero) digits is 1200, while the sum is 22.

The square root of 205435021 is about 14333.0046047575. The cubic root of 205435021 is about 590.0536396698.

Adding to 205435021 its reverse (120534502), we get a palindrome (325969523).

The spelling of 205435021 in words is "two hundred five million, four hundred thirty-five thousand, twenty-one".