21633441361 has 16 divisors (see below), whose sum is σ = 25815610368. Its totient is φ = 17725237200.

The previous prime is 21633441359. The next prime is 21633441377. The reversal of 21633441361 is 16314433612.

It is a cyclic number.

It is not a de Polignac number, because 21633441361 - 2¹ = 21633441359 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21633441461) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 210166 + ... + 295696.

It is an arithmetic number, because the mean of its divisors is an integer number (1613475648).

Almost surely, 2^21633441361 is an apocalyptic number.

It is an amenable number.

21633441361 is a deficient number, since it is larger than the sum of its proper divisors (4182169007).

21633441361 is a wasteful number, since it uses less digits than its factorization.

21633441361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87132.

The product of its digits is 31104, while the sum is 34.

Adding to 21633441361 its reverse (16314433612), we get a palindrome (37947874973).

The spelling of 21633441361 in words is "twenty-one billion, six hundred thirty-three million, four hundred forty-one thousand, three hundred sixty-one".