243697 has 4 divisors (see below), whose sum is σ = 244720. Its totient is φ = 242676.

The previous prime is 243673. The next prime is 243701. The reversal of 243697 is 796342.

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, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 796342 = 2 ⋅398171.

It is a cyclic number.

It is not a de Polignac number, because 243697 - 2¹⁵ = 210929 is a prime.

It is a d-powerful number, because it can be written as 2¹⁷ + 4⁸ + 6⁶ + 3⁴ + 9 + 7³ .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (243647) 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, 58 + ... + 700.

It is an arithmetic number, because the mean of its divisors is an integer number (61180).

2²⁴³⁶⁹⁷ is an apocalyptic number.

It is an amenable number.

243697 is a deficient number, since it is larger than the sum of its proper divisors (1023).

243697 is an equidigital number, since it uses as much as digits as its factorization.

243697 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1022.

The product of its digits is 9072, while the sum is 31.

The square root of 243697 is about 493.6567633488. The cubic root of 243697 is about 62.4621210476.

It can be divided in two parts, 24 and 3697, that added together give a square (3721 = 61²).

The spelling of 243697 in words is "two hundred forty-three thousand, six hundred ninety-seven".