205011251 has 4 divisors (see below), whose sum is σ = 206927352. Its totient is φ = 203095152.

The previous prime is 205011217. The next prime is 205011263. The reversal of 205011251 is 152110502.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 205011251 - 2¹⁰ = 205010227 is a prime.

It is a super-2 number, since 2×205011251² = 84059226073170002, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (205011271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 957890 + ... + 958103.

It is an arithmetic number, because the mean of its divisors is an integer number (51731838).

Almost surely, 2^205011251 is an apocalyptic number.

205011251 is a deficient number, since it is larger than the sum of its proper divisors (1916101).

205011251 is a wasteful number, since it uses less digits than its factorization.

205011251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1916100.

The product of its (nonzero) digits is 100, while the sum is 17.

The square root of 205011251 is about 14318.2139598485. The cubic root of 205011251 is about 589.6476407985.

Adding to 205011251 its reverse (152110502), we get a palindrome (357121753).

The spelling of 205011251 in words is "two hundred five million, eleven thousand, two hundred fifty-one".