21533431523245 has 16 divisors (see below), whose sum is σ = 26154352546560. Its totient is φ = 17017301565504.

The previous prime is 21533431523213. The next prime is 21533431523437. The reversal of 21533431523245 is 54232513433512.

It is a cyclic number.

It is not a de Polignac number, because 21533431523245 - 2⁵ = 21533431523213 is a prime.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 857491 + ... + 6618319.

It is an arithmetic number, because the mean of its divisors is an integer number (1634647034160).

Almost surely, 2^{21533431523245} is an apocalyptic number.

It is an amenable number.

21533431523245 is a deficient number, since it is larger than the sum of its proper divisors (4620921023315).

21533431523245 is an equidigital number, since it uses as much as digits as its factorization.

21533431523245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5769924.

The product of its digits is 1296000, while the sum is 43.

Adding to 21533431523245 its reverse (54232513433512), we get a palindrome (75765944956757).

The spelling of 21533431523245 in words is "twenty-one trillion, five hundred thirty-three billion, four hundred thirty-one million, five hundred twenty-three thousand, two hundred forty-five".