20447225 has 6 divisors (see below), whose sum is σ = 25354590. Its totient is φ = 16357760.

The previous prime is 20447191. The next prime is 20447239. The reversal of 20447225 is 52274402.

It can be written as a sum of positive squares in 3 ways, for example, as 769129 + 19678096 = 877^2 + 4436^2 .

It is not a de Polignac number, because 20447225 - 2⁸ = 20446969 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20447194 and 20447203.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 408920 + ... + 408969.

It is an arithmetic number, because the mean of its divisors is an integer number (4225765).

Almost surely, 2^20447225 is an apocalyptic number.

20447225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20447225 is a deficient number, since it is larger than the sum of its proper divisors (4907365).

20447225 is an equidigital number, since it uses as much as digits as its factorization.

20447225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 817899 (or 817894 counting only the distinct ones).

The product of its (nonzero) digits is 4480, while the sum is 26.

The square root of 20447225 is about 4521.8607895423. The cubic root of 20447225 is about 273.4501244239.

The spelling of 20447225 in words is "twenty million, four hundred forty-seven thousand, two hundred twenty-five".