21525223133 has 2 divisors, whose sum is σ = 21525223134. Its totient is φ = 21525223132.

The previous prime is 21525223123. The next prime is 21525223189. The reversal of 21525223133 is 33132252512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17455165924 + 4070057209 = 132118^2 + 63797^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21525223133 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21525223096 and 21525223105.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21525223123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10762611566 + 10762611567.

It is an arithmetic number, because the mean of its divisors is an integer number (10762611567).

Almost surely, 2^21525223133 is an apocalyptic number.

It is an amenable number.

21525223133 is a deficient number, since it is larger than the sum of its proper divisors (1).

21525223133 is an equidigital number, since it uses as much as digits as its factorization.

21525223133 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10800, while the sum is 29.

Adding to 21525223133 its reverse (33132252512), we get a palindrome (54657475645).

The spelling of 21525223133 in words is "twenty-one billion, five hundred twenty-five million, two hundred twenty-three thousand, one hundred thirty-three".