21202145453 has 4 divisors (see below), whose sum is σ = 22123977888. Its totient is φ = 20280313020.

The previous prime is 21202145431. The next prime is 21202145479. The reversal of 21202145453 is 35454120212.

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 not a de Polignac number, because 21202145453 - 2⁶ = 21202145389 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 (21202145413) 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, 460916183 + ... + 460916228.

It is an arithmetic number, because the mean of its divisors is an integer number (5530994472).

Almost surely, 2^21202145453 is an apocalyptic number.

21202145453 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21202145453 is a deficient number, since it is larger than the sum of its proper divisors (921832435).

21202145453 is an equidigital number, since it uses as much as digits as its factorization.

21202145453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 921832434.

The product of its (nonzero) digits is 9600, while the sum is 29.

Adding to 21202145453 its reverse (35454120212), we get a palindrome (56656265665).

The spelling of 21202145453 in words is "twenty-one billion, two hundred two million, one hundred forty-five thousand, four hundred fifty-three".