205241551 has 4 divisors (see below), whose sum is σ = 205524592. Its totient is φ = 204958512.

The previous prime is 205241513. The next prime is 205241573. The reversal of 205241551 is 155142502.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 155142502 = 2 ⋅77571251.

It is a cyclic number.

It is not a de Polignac number, because 205241551 - 2¹³ = 205233359 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205241501) 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, 140430 + ... + 141883.

It is an arithmetic number, because the mean of its divisors is an integer number (51381148).

Almost surely, 2^205241551 is an apocalyptic number.

205241551 is a deficient number, since it is larger than the sum of its proper divisors (283041).

205241551 is an equidigital number, since it uses as much as digits as its factorization.

205241551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 283040.

The product of its (nonzero) digits is 2000, while the sum is 25.

The square root of 205241551 is about 14326.2539067266. The cubic root of 205241551 is about 589.8683523185.

The spelling of 205241551 in words is "two hundred five million, two hundred forty-one thousand, five hundred fifty-one".