21503331453 has 8 divisors (see below), whose sum is σ = 30180114400. Its totient is φ = 13581051408.

The previous prime is 21503331439. The next prime is 21503331457. The reversal of 21503331453 is 35413330512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21503331453 - 2⁹ = 21503330941 is a prime.

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 21503331453.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21503331457) 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, 188625658 + ... + 188625771.

It is an arithmetic number, because the mean of its divisors is an integer number (3772514300).

Almost surely, 2^21503331453 is an apocalyptic number.

It is an amenable number.

21503331453 is a deficient number, since it is larger than the sum of its proper divisors (8676782947).

21503331453 is a wasteful number, since it uses less digits than its factorization.

21503331453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 377251451.

The product of its (nonzero) digits is 16200, while the sum is 30.

Adding to 21503331453 its reverse (35413330512), we get a palindrome (56916661965).

The spelling of 21503331453 in words is "twenty-one billion, five hundred three million, three hundred thirty-one thousand, four hundred fifty-three".