21225532205 has 4 divisors (see below), whose sum is σ = 25470638652. Its totient is φ = 16980425760.

The previous prime is 21225532201. The next prime is 21225532213. The reversal of 21225532205 is 50223552212.

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 2192018761 + 19033513444 = 46819^2 + 137962^2 .

It is not a de Polignac number, because 21225532205 - 2² = 21225532201 is a prime.

It is a super-5 number, since 5×21225532205⁵ (a number of 53 digits) contains 55555 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21225532201) 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 in 3 ways as a sum of consecutive naturals, for example, 2122553216 + ... + 2122553225.

It is an arithmetic number, because the mean of its divisors is an integer number (6367659663).

Almost surely, 2^21225532205 is an apocalyptic number.

It is an amenable number.

21225532205 is a deficient number, since it is larger than the sum of its proper divisors (4245106447).

21225532205 is an equidigital number, since it uses as much as digits as its factorization.

21225532205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4245106446.

The product of its (nonzero) digits is 12000, while the sum is 29.

The spelling of 21225532205 in words is "twenty-one billion, two hundred twenty-five million, five hundred thirty-two thousand, two hundred five".