205507121 has 4 divisors (see below), whose sum is σ = 205557744. Its totient is φ = 205456500.

The previous prime is 205507103. The next prime is 205507147. The reversal of 205507121 is 121705502.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 205507121 - 2¹⁴ = 205490737 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (205507721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18635 + ... + 27536.

It is an arithmetic number, because the mean of its divisors is an integer number (51389436).

Almost surely, 2^205507121 is an apocalyptic number.

It is an amenable number.

205507121 is a deficient number, since it is larger than the sum of its proper divisors (50623).

205507121 is an equidigital number, since it uses as much as digits as its factorization.

205507121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50622.

The product of its (nonzero) digits is 700, while the sum is 23.

The square root of 205507121 is about 14335.5195580767. The cubic root of 205507121 is about 590.1226605070.

The spelling of 205507121 in words is "two hundred five million, five hundred seven thousand, one hundred twenty-one".