21845715835 has 4 divisors (see below), whose sum is σ = 26214859008. Its totient is φ = 17476572664.

The previous prime is 21845715833. The next prime is 21845715839. The reversal of 21845715835 is 53851754812.

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

It is a cyclic number.

It is not a de Polignac number, because 21845715835 - 2¹ = 21845715833 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21845715833) 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, 2184571579 + ... + 2184571588.

It is an arithmetic number, because the mean of its divisors is an integer number (6553714752).

Almost surely, 2^21845715835 is an apocalyptic number.

21845715835 is a deficient number, since it is larger than the sum of its proper divisors (4369143173).

21845715835 is an equidigital number, since it uses as much as digits as its factorization.

21845715835 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4369143172.

The product of its digits is 1344000, while the sum is 49.

The spelling of 21845715835 in words is "twenty-one billion, eight hundred forty-five million, seven hundred fifteen thousand, eight hundred thirty-five".