221201425 has 6 divisors (see below), whose sum is σ = 274289798. Its totient is φ = 176961120.

The previous prime is 221201369. The next prime is 221201447. The reversal of 221201425 is 524102122.

It can be written as a sum of positive squares in 3 ways, for example, as 2989441 + 218211984 = 1729^2 + 14772^2 .

It is not a de Polignac number, because 221201425 - 2¹⁹ = 220677137 is a prime.

It is a Duffinian number.

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, 4424004 + ... + 4424053.

Almost surely, 2^221201425 is an apocalyptic number.

221201425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

221201425 is a deficient number, since it is larger than the sum of its proper divisors (53088373).

221201425 is an equidigital number, since it uses as much as digits as its factorization.

221201425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8848067 (or 8848062 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 19.

The square root of 221201425 is about 14872.8418602498. The cubic root of 221201425 is about 604.7779846988. Note that the first 3 decimals are identical.

Adding to 221201425 its reverse (524102122), we get a palindrome (745303547).

The spelling of 221201425 in words is "two hundred twenty-one million, two hundred one thousand, four hundred twenty-five".