243739157 has 4 divisors (see below), whose sum is σ = 244437900. Its totient is φ = 243040416.

The previous prime is 243739147. The next prime is 243739169. The reversal of 243739157 is 751937342.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 67141636 + 176597521 = 8194^2 + 13289^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243739157 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 (243739147) 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, 348848 + ... + 349545.

It is an arithmetic number, because the mean of its divisors is an integer number (61109475).

Almost surely, 2^243739157 is an apocalyptic number.

It is an amenable number.

243739157 is a deficient number, since it is larger than the sum of its proper divisors (698743).

243739157 is an equidigital number, since it uses as much as digits as its factorization.

243739157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 698742.

The product of its digits is 158760, while the sum is 41.

The square root of 243739157 is about 15612.1477382197. The cubic root of 243739157 is about 624.6572260173.

The spelling of 243739157 in words is "two hundred forty-three million, seven hundred thirty-nine thousand, one hundred fifty-seven".