243021655 has 8 divisors (see below), whose sum is σ = 294513984. Its totient is φ = 192492000.

The previous prime is 243021619. The next prime is 243021659. The reversal of 243021655 is 556120342.

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-243021655 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 (243021659) 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, 240111 + ... + 241120.

It is an arithmetic number, because the mean of its divisors is an integer number (36814248).

Almost surely, 2^243021655 is an apocalyptic number.

243021655 is a deficient number, since it is larger than the sum of its proper divisors (51492329).

243021655 is a wasteful number, since it uses less digits than its factorization.

243021655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 481337.

The product of its (nonzero) digits is 7200, while the sum is 28.

The square root of 243021655 is about 15589.1518370949. The cubic root of 243021655 is about 624.0436830790.

Adding to 243021655 its reverse (556120342), we get a palindrome (799141997).

The spelling of 243021655 in words is "two hundred forty-three million, twenty-one thousand, six hundred fifty-five".