243513120645 has 24 divisors (see below), whose sum is σ = 424777889016. Its totient is φ = 129046439808.

The previous prime is 243513120637. The next prime is 243513120649. The reversal of 243513120645 is 546021315342.

243513120645 is a `hidden beast` number, since 2 + 4 + 3 + 5 + 1 + 3 + 1 + 2 + 0 + 645 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1974291489 + 241538829156 = 44433^2 + 491466^2 .

It is not a de Polignac number, because 243513120645 - 2³ = 243513120637 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243513120649) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17226702 + ... + 17240831.

It is an arithmetic number, because the mean of its divisors is an integer number (17699078709).

Almost surely, 2^243513120645 is an apocalyptic number.

It is an amenable number.

243513120645 is a deficient number, since it is larger than the sum of its proper divisors (181264768371).

243513120645 is a wasteful number, since it uses less digits than its factorization.

243513120645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34467701 (or 34467698 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 36.

Adding to 243513120645 its reverse (546021315342), we get a palindrome (789534435987).

The spelling of 243513120645 in words is "two hundred forty-three billion, five hundred thirteen million, one hundred twenty thousand, six hundred forty-five".