21530350453 has 4 divisors (see below), whose sum is σ = 21531519360. Its totient is φ = 21529181548.

The previous prime is 21530350427. The next prime is 21530350481. The reversal of 21530350453 is 35405303512.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21530350453 - 2¹³ = 21530342261 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21500350453) 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 3 ways as a sum of consecutive naturals, for example, 556375 + ... + 593812.

It is an arithmetic number, because the mean of its divisors is an integer number (5382879840).

Almost surely, 2^21530350453 is an apocalyptic number.

It is an amenable number.

21530350453 is a deficient number, since it is larger than the sum of its proper divisors (1168907).

21530350453 is a wasteful number, since it uses less digits than its factorization.

21530350453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1168906.

The product of its (nonzero) digits is 27000, while the sum is 31.

Adding to 21530350453 its reverse (35405303512), we get a palindrome (56935653965).

The spelling of 21530350453 in words is "twenty-one billion, five hundred thirty million, three hundred fifty thousand, four hundred fifty-three".