243796821 has 8 divisors (see below), whose sum is σ = 325168704. Its totient is φ = 162478080.

The previous prime is 243796801. The next prime is 243796829. The reversal of 243796821 is 128697342.

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

It is a de Polignac number, because none of the positive numbers 2^k-243796821 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243796829) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 940 + ... + 22101.

It is an arithmetic number, because the mean of its divisors is an integer number (40646088).

Almost surely, 2^243796821 is an apocalyptic number.

It is an amenable number.

243796821 is a deficient number, since it is larger than the sum of its proper divisors (81371883).

243796821 is a wasteful number, since it uses less digits than its factorization.

243796821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26571.

The product of its digits is 145152, while the sum is 42.

The square root of 243796821 is about 15613.9943960538. The cubic root of 243796821 is about 624.7064827645.

The spelling of 243796821 in words is "two hundred forty-three million, seven hundred ninety-six thousand, eight hundred twenty-one".