243851913 has 6 divisors (see below), whose sum is σ = 352230554. Its totient is φ = 162567936.

The previous prime is 243851899. The next prime is 243851987. The reversal of 243851913 is 319158342.

It can be written as a sum of positive squares in only one way, i.e., 207273609 + 36578304 = 14397^2 + 6048^2 .

It is not a de Polignac number, because 243851913 - 2¹⁰ = 243850889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (243851513) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 13547320 + ... + 13547337.

Almost surely, 2^243851913 is an apocalyptic number.

It is an amenable number.

243851913 is a deficient number, since it is larger than the sum of its proper divisors (108378641).

243851913 is a wasteful number, since it uses less digits than its factorization.

243851913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27094663 (or 27094660 counting only the distinct ones).

The product of its digits is 25920, while the sum is 36.

The square root of 243851913 is about 15615.7584830196. The cubic root of 243851913 is about 624.7535352476.

The spelling of 243851913 in words is "two hundred forty-three million, eight hundred fifty-one thousand, nine hundred thirteen".