21220010011205 has 8 divisors (see below), whose sum is σ = 26342081393400. Its totient is φ = 16390628422336.

The previous prime is 21220010011181. The next prime is 21220010011247. The reversal of 21220010011205 is 50211001002212.

It can be written as a sum of positive squares in 4 ways, for example, as 16259820196 + 21203750191009 = 127514^2 + 4604753^2 .

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 21220010011205 - 2⁶ = 21220010011141 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 73172448170 + ... + 73172448459.

It is an arithmetic number, because the mean of its divisors is an integer number (3292760174175).

Almost surely, 2^{21220010011205} is an apocalyptic number.

It is an amenable number.

21220010011205 is a deficient number, since it is larger than the sum of its proper divisors (5122071382195).

21220010011205 is a wasteful number, since it uses less digits than its factorization.

21220010011205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 146344896663.

The product of its (nonzero) digits is 80, while the sum is 17.

Adding to 21220010011205 its reverse (50211001002212), we get a palindrome (71431011013417).

The spelling of 21220010011205 in words is "twenty-one trillion, two hundred twenty billion, ten million, eleven thousand, two hundred five".