21473556163 has 4 divisors (see below), whose sum is σ = 21776000688. Its totient is φ = 21171111640.

The previous prime is 21473556133. The next prime is 21473556197. The reversal of 21473556163 is 36165537412.

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 21473556163 - 2⁹ = 21473555651 is a prime.

It is a super-2 number, since 2×21473556163² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21473556133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 151222156 + ... + 151222297.

It is an arithmetic number, because the mean of its divisors is an integer number (5444000172).

Almost surely, 2^21473556163 is an apocalyptic number.

21473556163 is a deficient number, since it is larger than the sum of its proper divisors (302444525).

21473556163 is an equidigital number, since it uses as much as digits as its factorization.

21473556163 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 302444524.

The product of its digits is 453600, while the sum is 43.

The spelling of 21473556163 in words is "twenty-one billion, four hundred seventy-three million, five hundred fifty-six thousand, one hundred sixty-three".