21603510453 has 16 divisors (see below), whose sum is σ = 32925639296. Its totient is φ = 12342611520.

The previous prime is 21603510437. The next prime is 21603510463. The reversal of 21603510453 is 35401530612.

It is not a de Polignac number, because 21603510453 - 2⁴ = 21603510437 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21603510453.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21603510463) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27723 + ... + 209703.

It is an arithmetic number, because the mean of its divisors is an integer number (2057852456).

Almost surely, 2^21603510453 is an apocalyptic number.

It is an amenable number.

21603510453 is a deficient number, since it is larger than the sum of its proper divisors (11322128843).

21603510453 is a wasteful number, since it uses less digits than its factorization.

21603510453 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187644.

The product of its (nonzero) digits is 10800, while the sum is 30.

The spelling of 21603510453 in words is "twenty-one billion, six hundred three million, five hundred ten thousand, four hundred fifty-three".