21168168243 has 32 divisors (see below), whose sum is σ = 29907947520. Its totient is φ = 13290562560.

The previous prime is 21168168227. The next prime is 21168168257. The reversal of 21168168243 is 34286186112.

It is a happy number.

It is not a de Polignac number, because 21168168243 - 2⁴ = 21168168227 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21168168195 and 21168168204.

It is not an unprimeable number, because it can be changed into a prime (21168161243) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1472830 + ... + 1487132.

It is an arithmetic number, because the mean of its divisors is an integer number (934623360).

Almost surely, 2^21168168243 is an apocalyptic number.

21168168243 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21168168243 is a deficient number, since it is larger than the sum of its proper divisors (8739779277).

21168168243 is a wasteful number, since it uses less digits than its factorization.

21168168243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14659.

The product of its digits is 110592, while the sum is 42.

The spelling of 21168168243 in words is "twenty-one billion, one hundred sixty-eight million, one hundred sixty-eight thousand, two hundred forty-three".