21213566234167 has 2 divisors, whose sum is σ = 21213566234168. Its totient is φ = 21213566234166.

The previous prime is 21213566234153. The next prime is 21213566234291. The reversal of 21213566234167 is 76143266531212.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21213566234167 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21213566234167.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21213566231167) 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 as a sum of consecutive naturals, namely, 10606783117083 + 10606783117084.

It is an arithmetic number, because the mean of its divisors is an integer number (10606783117084).

Almost surely, 2^{21213566234167} is an apocalyptic number.

21213566234167 is a deficient number, since it is larger than the sum of its proper divisors (1).

21213566234167 is an equidigital number, since it uses as much as digits as its factorization.

21213566234167 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2177280, while the sum is 49.

The spelling of 21213566234167 in words is "twenty-one trillion, two hundred thirteen billion, five hundred sixty-six million, two hundred thirty-four thousand, one hundred sixty-seven".