21818314059505 has 8 divisors (see below), whose sum is σ = 26187851247912. Its totient is φ = 17450734996608.

The previous prime is 21818314059497. The next prime is 21818314059557. The reversal of 21818314059505 is 50595041381812.

It can be written as a sum of positive squares in 4 ways, for example, as 6523738413921 + 15294575645584 = 2554161^2 + 3910828^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21818314059505 - 2³ = 21818314059497 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 489506862 + ... + 489551431.

It is an arithmetic number, because the mean of its divisors is an integer number (3273481405989).

Almost surely, 2^{21818314059505} is an apocalyptic number.

It is an amenable number.

21818314059505 is a deficient number, since it is larger than the sum of its proper divisors (4369537188407).

21818314059505 is an equidigital number, since it uses as much as digits as its factorization.

21818314059505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 979062755.

The product of its (nonzero) digits is 1728000, while the sum is 52.

The spelling of 21818314059505 in words is "twenty-one trillion, eight hundred eighteen billion, three hundred fourteen million, fifty-nine thousand, five hundred five".