21825245563 has 4 divisors (see below), whose sum is σ = 23809358808. Its totient is φ = 19841132320.

The previous prime is 21825245543. The next prime is 21825245621. The reversal of 21825245563 is 36554252812.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21825245563 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21825245543) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 992056606 + ... + 992056627.

It is an arithmetic number, because the mean of its divisors is an integer number (5952339702).

Almost surely, 2^21825245563 is an apocalyptic number.

21825245563 is a deficient number, since it is larger than the sum of its proper divisors (1984113245).

21825245563 is a wasteful number, since it uses less digits than its factorization.

21825245563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1984113244.

The product of its digits is 576000, while the sum is 43.

The spelling of 21825245563 in words is "twenty-one billion, eight hundred twenty-five million, two hundred forty-five thousand, five hundred sixty-three".