21858184013 has 2 divisors, whose sum is σ = 21858184014. Its totient is φ = 21858184012.

The previous prime is 21858183961. The next prime is 21858184069. The reversal of 21858184013 is 31048185812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20415551689 + 1442632324 = 142883^2 + 37982^2 .

It is a cyclic number.

It is not a de Polignac number, because 21858184013 - 2²⁰ = 21857135437 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21858184913) 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 as a sum of consecutive naturals, namely, 10929092006 + 10929092007.

It is an arithmetic number, because the mean of its divisors is an integer number (10929092007).

Almost surely, 2^21858184013 is an apocalyptic number.

It is an amenable number.

21858184013 is a deficient number, since it is larger than the sum of its proper divisors (1).

21858184013 is an equidigital number, since it uses as much as digits as its factorization.

21858184013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 61440, while the sum is 41.

The spelling of 21858184013 in words is "twenty-one billion, eight hundred fifty-eight million, one hundred eighty-four thousand, thirteen".