21653037453503 has 4 divisors (see below), whose sum is σ = 21664993853688. Its totient is φ = 21641081053320.

The previous prime is 21653037453461. The next prime is 21653037453511. The reversal of 21653037453503 is 30535473035612.

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 21653037453503 - 2¹⁰ = 21653037452479 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 (21653037453583) 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, 5978197376 + ... + 5978200997.

It is an arithmetic number, because the mean of its divisors is an integer number (5416248463422).

Almost surely, 2^{21653037453503} is an apocalyptic number.

21653037453503 is a deficient number, since it is larger than the sum of its proper divisors (11956400185).

21653037453503 is a wasteful number, since it uses less digits than its factorization.

21653037453503 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11956400184.

The product of its (nonzero) digits is 3402000, while the sum is 47.

The spelling of 21653037453503 in words is "twenty-one trillion, six hundred fifty-three billion, thirty-seven million, four hundred fifty-three thousand, five hundred three".