21468514561 has 16 divisors (see below), whose sum is σ = 24564254400. Its totient is φ = 18598603968.

The previous prime is 21468514559. The next prime is 21468514607. The reversal of 21468514561 is 16541586412.

It is a cyclic number.

It is not a de Polignac number, because 21468514561 - 2¹ = 21468514559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21468514261) 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 15 ways as a sum of consecutive naturals, for example, 379726 + ... + 432583.

It is an arithmetic number, because the mean of its divisors is an integer number (1535265900).

Almost surely, 2^21468514561 is an apocalyptic number.

It is an amenable number.

21468514561 is a deficient number, since it is larger than the sum of its proper divisors (3095739839).

21468514561 is a wasteful number, since it uses less digits than its factorization.

21468514561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 812448.

The product of its digits is 230400, while the sum is 43.

The spelling of 21468514561 in words is "twenty-one billion, four hundred sixty-eight million, five hundred fourteen thousand, five hundred sixty-one".