243749823 has 4 divisors (see below), whose sum is σ = 324999768. Its totient is φ = 162499880.

The previous prime is 243749801. The next prime is 243749861. The reversal of 243749823 is 328947342.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243749823 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243739823) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40624968 + ... + 40624973.

It is an arithmetic number, because the mean of its divisors is an integer number (81249942).

Almost surely, 2^243749823 is an apocalyptic number.

243749823 is a deficient number, since it is larger than the sum of its proper divisors (81249945).

243749823 is an equidigital number, since it uses as much as digits as its factorization.

243749823 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81249944.

The product of its digits is 290304, while the sum is 42.

The square root of 243749823 is about 15612.4893274583. The cubic root of 243749823 is about 624.6663375293. Note that the first 3 decimals are identical.

The spelling of 243749823 in words is "two hundred forty-three million, seven hundred forty-nine thousand, eight hundred twenty-three".