243053551 has 4 divisors (see below), whose sum is σ = 261749992. Its totient is φ = 224357112.

The previous prime is 243053549. The next prime is 243053557. The reversal of 243053551 is 155350342.

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 243053551 - 2¹ = 243053549 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 (243053557) 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, 9348201 + ... + 9348226.

It is an arithmetic number, because the mean of its divisors is an integer number (65437498).

Almost surely, 2^243053551 is an apocalyptic number.

243053551 is a deficient number, since it is larger than the sum of its proper divisors (18696441).

243053551 is a wasteful number, since it uses less digits than its factorization.

243053551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18696440.

The product of its (nonzero) digits is 9000, while the sum is 28.

The square root of 243053551 is about 15590.1748226247. The cubic root of 243053551 is about 624.0709832889.

The spelling of 243053551 in words is "two hundred forty-three million, fifty-three thousand, five hundred fifty-one".