21533414455123 has 4 divisors (see below), whose sum is σ = 21533436574720. Its totient is φ = 21533392335528.

The previous prime is 21533414455121. The next prime is 21533414455177. The reversal of 21533414455123 is 32155441433512.

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

It is a cyclic number.

It is not a de Polignac number, because 21533414455123 - 2¹ = 21533414455121 is a prime.

It is a super-2 number, since 2×21533414455123² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21533414455123.

It is not an unprimeable number, because it can be changed into a prime (21533414455121) 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, 9528915 + ... + 11570092.

It is an arithmetic number, because the mean of its divisors is an integer number (5383359143680).

Almost surely, 2^{21533414455123} is an apocalyptic number.

21533414455123 is a deficient number, since it is larger than the sum of its proper divisors (22119597).

21533414455123 is a wasteful number, since it uses less digits than its factorization.

21533414455123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22119596.

The product of its digits is 864000, while the sum is 43.

Adding to 21533414455123 its reverse (32155441433512), we get a palindrome (53688855888635).

The spelling of 21533414455123 in words is "twenty-one trillion, five hundred thirty-three billion, four hundred fourteen million, four hundred fifty-five thousand, one hundred twenty-three".