243404241021 has 6 divisors (see below), whose sum is σ = 351583903710. Its totient is φ = 162269494008.

The previous prime is 243404240953. The next prime is 243404241023. The reversal of 243404241021 is 120142404342.

243404241021 is a `hidden beast` number, since 243 + 4 + 0 + 4 + 2 + 410 + 2 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 187306318521 + 56097922500 = 432789^2 + 236850^2 .

It is not a de Polignac number, because 243404241021 - 2¹³ = 243404232829 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243404241023) 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, 13522457826 + ... + 13522457843.

It is an arithmetic number, because the mean of its divisors is an integer number (58597317285).

Almost surely, 2^243404241021 is an apocalyptic number.

It is an amenable number.

243404241021 is a deficient number, since it is larger than the sum of its proper divisors (108179662689).

243404241021 is a wasteful number, since it uses less digits than its factorization.

243404241021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27044915675 (or 27044915672 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 27.

Adding to 243404241021 its reverse (120142404342), we get a palindrome (363546645363).

The spelling of 243404241021 in words is "two hundred forty-three billion, four hundred four million, two hundred forty-one thousand, twenty-one".