20928225 has 24 divisors (see below), whose sum is σ = 34765632. Its totient is φ = 11108800.

The previous prime is 20928223. The next prime is 20928239. The reversal of 20928225 is 52282902.

It is not a de Polignac number, because 20928225 - 2¹ = 20928223 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20928192 and 20928201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20928223) 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, 19195 + ... + 20255.

It is an arithmetic number, because the mean of its divisors is an integer number (1448568).

Almost surely, 2^20928225 is an apocalyptic number.

20928225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20928225 is a deficient number, since it is larger than the sum of its proper divisors (13837407).

20928225 is a wasteful number, since it uses less digits than its factorization.

20928225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1337 (or 1332 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 20928225 is about 4574.7376973986. The cubic root of 20928225 is about 275.5777385659.

The spelling of 20928225 in words is "twenty million, nine hundred twenty-eight thousand, two hundred twenty-five".