21717243453 has 16 divisors (see below), whose sum is σ = 30663112896. Its totient is φ = 13624961280.

The previous prime is 21717243451. The next prime is 21717243461. The reversal of 21717243453 is 35434271712.

It is not a de Polignac number, because 21717243453 - 2¹ = 21717243451 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21717243451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 574350 + ... + 610992.

It is an arithmetic number, because the mean of its divisors is an integer number (1916444556).

Almost surely, 2^21717243453 is an apocalyptic number.

It is an amenable number.

21717243453 is a deficient number, since it is larger than the sum of its proper divisors (8945869443).

21717243453 is a wasteful number, since it uses less digits than its factorization.

21717243453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48284.

The product of its digits is 141120, while the sum is 39.

The spelling of 21717243453 in words is "twenty-one billion, seven hundred seventeen million, two hundred forty-three thousand, four hundred fifty-three".