205621121 has 8 divisors (see below), whose sum is σ = 208790400. Its totient is φ = 202466160.

The previous prime is 205621093. The next prime is 205621123. The reversal of 205621121 is 121126502.

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 205621121 - 2¹⁰ = 205620097 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 205621093 and 205621102.

It is not an unprimeable number, because it can be changed into a prime (205621123) 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, 27386 + ... + 34076.

It is an arithmetic number, because the mean of its divisors is an integer number (26098800).

Almost surely, 2^205621121 is an apocalyptic number.

It is an amenable number.

205621121 is a deficient number, since it is larger than the sum of its proper divisors (3169279).

205621121 is an equidigital number, since it uses as much as digits as its factorization.

205621121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7159.

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 205621121 is about 14339.4951445300. The cubic root of 205621121 is about 590.2317589935.

Adding to 205621121 its reverse (121126502), we get a palindrome (326747623).

The spelling of 205621121 in words is "two hundred five million, six hundred twenty-one thousand, one hundred twenty-one".