20641225 has 24 divisors (see below), whose sum is σ = 28533888. Its totient is φ = 14683200.

The previous prime is 20641223. The next prime is 20641253. The reversal of 20641225 is 52214602.

It is not a de Polignac number, because 20641225 - 2¹ = 20641223 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20641196 and 20641205.

It is not an unprimeable number, because it can be changed into a prime (20641223) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12127 + ... + 13723.

It is an arithmetic number, because the mean of its divisors is an integer number (1188912).

Almost surely, 2^20641225 is an apocalyptic number.

20641225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20641225 is a deficient number, since it is larger than the sum of its proper divisors (7892663).

20641225 is a wasteful number, since it uses less digits than its factorization.

20641225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1665 (or 1660 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 20641225 is about 4543.2614936849. The cubic root of 20641225 is about 274.3122206811.

Adding to 20641225 its reverse (52214602), we get a palindrome (72855827).

The spelling of 20641225 in words is "twenty million, six hundred forty-one thousand, two hundred twenty-five".