21168543051 has 32 divisors (see below), whose sum is σ = 33420625920. Its totient is φ = 13211554752.

The previous prime is 21168543049. The next prime is 21168543073. The reversal of 21168543051 is 15034586112.

21168543051 is a `hidden beast` number, since 2 + 1 + 1 + 68 + 543 + 0 + 51 = 666.

It is not a de Polignac number, because 21168543051 - 2¹ = 21168543049 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21168542997 and 21168543015.

It is not an unprimeable number, because it can be changed into a prime (21168543551) 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, 333450 + ... + 391823.

It is an arithmetic number, because the mean of its divisors is an integer number (1044394560).

Almost surely, 2^21168543051 is an apocalyptic number.

21168543051 is a deficient number, since it is larger than the sum of its proper divisors (12252082869).

21168543051 is a wasteful number, since it uses less digits than its factorization.

21168543051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 725352 (or 725346 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

The spelling of 21168543051 in words is "twenty-one billion, one hundred sixty-eight million, five hundred forty-three thousand, fifty-one".