21520523215433 has 8 divisors (see below), whose sum is σ = 23477484959136. Its totient is φ = 19563653228800.

The previous prime is 21520523215379. The next prime is 21520523215439. The reversal of 21520523215433 is 33451232502512.

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 21520523215433 - 2²⁸ = 21520254779977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21520523215439) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22448408 + ... + 23387433.

It is an arithmetic number, because the mean of its divisors is an integer number (2934685619892).

Almost surely, 2^{21520523215433} is an apocalyptic number.

It is an amenable number.

21520523215433 is a deficient number, since it is larger than the sum of its proper divisors (1956961743703).

21520523215433 is a wasteful number, since it uses less digits than its factorization.

21520523215433 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45878535.

The product of its (nonzero) digits is 216000, while the sum is 38.

Adding to 21520523215433 its reverse (33451232502512), we get a palindrome (54971755717945).

The spelling of 21520523215433 in words is "twenty-one trillion, five hundred twenty billion, five hundred twenty-three million, two hundred fifteen thousand, four hundred thirty-three".