21724063663 has 8 divisors (see below), whose sum is σ = 22007278656. Its totient is φ = 21442444800.

The previous prime is 21724063597. The next prime is 21724063693. The reversal of 21724063663 is 36636042712.

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

It is not a de Polignac number, because 21724063663 - 2¹⁷ = 21723932591 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 (21724063693) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 371623 + ... + 426088.

It is an arithmetic number, because the mean of its divisors is an integer number (2750909832).

Almost surely, 2^21724063663 is an apocalyptic number.

21724063663 is a deficient number, since it is larger than the sum of its proper divisors (283214993).

21724063663 is a wasteful number, since it uses less digits than its factorization.

21724063663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 798065.

The product of its (nonzero) digits is 217728, while the sum is 40.

The spelling of 21724063663 in words is "twenty-one billion, seven hundred twenty-four million, sixty-three thousand, six hundred sixty-three".