21204303243442 has 16 divisors (see below), whose sum is σ = 34698085152192. Its totient is φ = 9638282325520.

The previous prime is 21204303243437. The next prime is 21204303243463. The reversal of 21204303243442 is 24434230340212.

It is a super-2 number, since 2×21204303243442² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21204303243398 and 21204303243407.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4412028 + ... + 7866040.

It is an arithmetic number, because the mean of its divisors is an integer number (2168630322012).

Almost surely, 2^{21204303243442} is an apocalyptic number.

21204303243442 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21204303243442 is a deficient number, since it is larger than the sum of its proper divisors (13493781908750).

21204303243442 is a wasteful number, since it uses less digits than its factorization.

21204303243442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3733073.

The product of its (nonzero) digits is 110592, while the sum is 34.

Adding to 21204303243442 its reverse (24434230340212), we get a palindrome (45638533583654).

The spelling of 21204303243442 in words is "twenty-one trillion, two hundred four billion, three hundred three million, two hundred forty-three thousand, four hundred forty-two".