21463744541 has 4 divisors (see below), whose sum is σ = 21704910300. Its totient is φ = 21222578784.

The previous prime is 21463744517. The next prime is 21463744543. The reversal of 21463744541 is 14544736412.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6950723641 + 14513020900 = 83371^2 + 120470^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21463744541 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21463744543) 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 3 ways as a sum of consecutive naturals, for example, 120582746 + ... + 120582923.

It is an arithmetic number, because the mean of its divisors is an integer number (5426227575).

Almost surely, 2^21463744541 is an apocalyptic number.

It is an amenable number.

21463744541 is a deficient number, since it is larger than the sum of its proper divisors (241165759).

21463744541 is an equidigital number, since it uses as much as digits as its factorization.

21463744541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 241165758.

The product of its digits is 322560, while the sum is 41.

The spelling of 21463744541 in words is "twenty-one billion, four hundred sixty-three million, seven hundred forty-four thousand, five hundred forty-one".