21845876845 has 8 divisors (see below), whose sum is σ = 28231594776. Its totient is φ = 16132339776.

The previous prime is 21845876839. The next prime is 21845876849. The reversal of 21845876845 is 54867854812.

It can be written as a sum of positive squares in 4 ways, for example, as 916757284 + 20929119561 = 30278^2 + 144669^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21845876845 - 2¹¹ = 21845874797 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21845876845.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21845876849) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 168045142 + ... + 168045271.

It is an arithmetic number, because the mean of its divisors is an integer number (3528949347).

Almost surely, 2^21845876845 is an apocalyptic number.

It is an amenable number.

21845876845 is a deficient number, since it is larger than the sum of its proper divisors (6385717931).

21845876845 is a wasteful number, since it uses less digits than its factorization.

21845876845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 336090431.

The product of its digits is 17203200, while the sum is 58.

The spelling of 21845876845 in words is "twenty-one billion, eight hundred forty-five million, eight hundred seventy-six thousand, eight hundred forty-five".