243120215531 has 8 divisors (see below), whose sum is σ = 244075608480. Its totient is φ = 242166008448.

The previous prime is 243120215491. The next prime is 243120215539. The reversal of 243120215531 is 135512021342.

243120215531 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 243120215531 - 2²² = 243116021227 is a prime.

It is a super-2 number, since 2×243120215531² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 243120215494 and 243120215503.

It is not an unprimeable number, because it can be changed into a prime (243120215539) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 115490 + ... + 706808.

It is an arithmetic number, because the mean of its divisors is an integer number (30509451060).

Almost surely, 2^243120215531 is an apocalyptic number.

243120215531 is a deficient number, since it is larger than the sum of its proper divisors (955392949).

243120215531 is a wasteful number, since it uses less digits than its factorization.

243120215531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 592933.

The product of its (nonzero) digits is 7200, while the sum is 29.

Adding to 243120215531 its reverse (135512021342), we get a palindrome (378632236873).

The spelling of 243120215531 in words is "two hundred forty-three billion, one hundred twenty million, two hundred fifteen thousand, five hundred thirty-one".