21000000132205 has 4 divisors (see below), whose sum is σ = 25200000158652. Its totient is φ = 16800000105760.

The previous prime is 21000000132149. The next prime is 21000000132239. The reversal of 21000000132205 is 50223100000012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16169582984164 + 4830417148041 = 4021142^2 + 2197821^2 .

It is not a de Polignac number, because 21000000132205 - 2¹¹ = 21000000130157 is a prime.

It is a super-2 number, since 2×21000000132205² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2100000013216 + ... + 2100000013225.

It is an arithmetic number, because the mean of its divisors is an integer number (6300000039663).

Almost surely, 2^{21000000132205} is an apocalyptic number.

It is an amenable number.

21000000132205 is a deficient number, since it is larger than the sum of its proper divisors (4200000026447).

21000000132205 is an equidigital number, since it uses as much as digits as its factorization.

21000000132205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4200000026446.

The product of its (nonzero) digits is 120, while the sum is 16.

Adding to 21000000132205 its reverse (50223100000012), we get a palindrome (71223100132217).

The spelling of 21000000132205 in words is "twenty-one trillion, one hundred thirty-two thousand, two hundred five".