243320511541 has 4 divisors (see below), whose sum is σ = 243453402784. Its totient is φ = 243187620300.

The previous prime is 243320511493. The next prime is 243320511557. The reversal of 243320511541 is 145115023342.

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 an emirpimes, since its reverse is a distinct semiprime: 145115023342 = 2 ⋅72557511671.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243320511541 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 (243320571541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66442875 + ... + 66446536.

It is an arithmetic number, because the mean of its divisors is an integer number (60863350696).

Almost surely, 2^243320511541 is an apocalyptic number.

It is an amenable number.

243320511541 is a deficient number, since it is larger than the sum of its proper divisors (132891243).

243320511541 is a wasteful number, since it uses less digits than its factorization.

243320511541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132891242.

The product of its (nonzero) digits is 14400, while the sum is 31.

Adding to 243320511541 its reverse (145115023342), we get a palindrome (388435534883).

The spelling of 243320511541 in words is "two hundred forty-three billion, three hundred twenty million, five hundred eleven thousand, five hundred forty-one".