20265221 has 4 divisors (see below), whose sum is σ = 20344332. Its totient is φ = 20186112.

The previous prime is 20265199. The next prime is 20265247. The reversal of 20265221 is 12256202.

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 10962721 + 9302500 = 3311^2 + 3050^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20265221 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20265193 and 20265202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20265121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39170 + ... + 39683.

It is an arithmetic number, because the mean of its divisors is an integer number (5086083).

Almost surely, 2^20265221 is an apocalyptic number.

It is an amenable number.

20265221 is a deficient number, since it is larger than the sum of its proper divisors (79111).

20265221 is an equidigital number, since it uses as much as digits as its factorization.

20265221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79110.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 20265221 is about 4501.6909045380. The cubic root of 20265221 is about 272.6363641485.

The spelling of 20265221 in words is "twenty million, two hundred sixty-five thousand, two hundred twenty-one".