21306105361 has 32 divisors (see below), whose sum is σ = 22963765248. Its totient is φ = 19722890880.

The previous prime is 21306105349. The next prime is 21306105383. The reversal of 21306105361 is 16350160312.

It is a cyclic number.

It is not a de Polignac number, because 21306105361 - 2⁹ = 21306104849 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21306105461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 43749460 + ... + 43749946.

It is an arithmetic number, because the mean of its divisors is an integer number (717617664).

Almost surely, 2^21306105361 is an apocalyptic number.

It is an amenable number.

21306105361 is a deficient number, since it is larger than the sum of its proper divisors (1657659887).

21306105361 is a wasteful number, since it uses less digits than its factorization.

21306105361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1021.

The product of its (nonzero) digits is 3240, while the sum is 28.

Adding to 21306105361 its reverse (16350160312), we get a palindrome (37656265673).

The spelling of 21306105361 in words is "twenty-one billion, three hundred six million, one hundred five thousand, three hundred sixty-one".