21006663163 has 8 divisors (see below), whose sum is σ = 21945594528. Its totient is φ = 20069865024.

The previous prime is 21006663151. The next prime is 21006663179. The reversal of 21006663163 is 36136660012.

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

It is a cyclic number.

It is not a de Polignac number, because 21006663163 - 2¹⁷ = 21006532091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21006663263) 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 7 ways as a sum of consecutive naturals, for example, 513156 + ... + 552577.

It is an arithmetic number, because the mean of its divisors is an integer number (2743199316).

Almost surely, 2^21006663163 is an apocalyptic number.

21006663163 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21006663163 is a deficient number, since it is larger than the sum of its proper divisors (938931365).

21006663163 is a wasteful number, since it uses less digits than its factorization.

21006663163 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1066613.

The product of its (nonzero) digits is 23328, while the sum is 34.

The spelling of 21006663163 in words is "twenty-one billion, six million, six hundred sixty-three thousand, one hundred sixty-three".