21122372563 has 4 divisors (see below), whose sum is σ = 21309296328. Its totient is φ = 20935448800.

The previous prime is 21122372533. The next prime is 21122372573. The reversal of 21122372563 is 36527322112.

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-21122372563 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21122372503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 93461713 + ... + 93461938.

It is an arithmetic number, because the mean of its divisors is an integer number (5327324082).

Almost surely, 2^21122372563 is an apocalyptic number.

21122372563 is a deficient number, since it is larger than the sum of its proper divisors (186923765).

21122372563 is a wasteful number, since it uses less digits than its factorization.

21122372563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186923764.

The product of its digits is 30240, while the sum is 34.

Adding to 21122372563 its reverse (36527322112), we get a palindrome (57649694675).

The spelling of 21122372563 in words is "twenty-one billion, one hundred twenty-two million, three hundred seventy-two thousand, five hundred sixty-three".