21204337361 has 8 divisors (see below), whose sum is σ = 21749423400. Its totient is φ = 20664621952.

The previous prime is 21204337351. The next prime is 21204337367. The reversal of 21204337361 is 16373340212.

It can be written as a sum of positive squares in 4 ways, for example, as 4977361 + 21199360000 = 2231^2 + 145600^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21204337361 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21204337367) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1334660 + ... + 1350453.

It is an arithmetic number, because the mean of its divisors is an integer number (2718677925).

Almost surely, 2^21204337361 is an apocalyptic number.

It is an amenable number.

21204337361 is a deficient number, since it is larger than the sum of its proper divisors (545086039).

21204337361 is a wasteful number, since it uses less digits than its factorization.

21204337361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2685315.

The product of its (nonzero) digits is 18144, while the sum is 32.

Adding to 21204337361 its reverse (16373340212), we get a palindrome (37577677573).

The spelling of 21204337361 in words is "twenty-one billion, two hundred four million, three hundred thirty-seven thousand, three hundred sixty-one".