221025 has 24 divisors (see below), whose sum is σ = 418624. Its totient is φ = 100800.

The previous prime is 221021. The next prime is 221047. The reversal of 221025 is 520122.

It is not a de Polignac number, because 221025 - 2² = 221021 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 221025.

It is not an unprimeable number, because it can be changed into a prime (221021) 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 23 ways as a sum of consecutive naturals, for example, 315 + ... + 735.

2²²¹⁰²⁵ is an apocalyptic number.

221025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

221025 is a deficient number, since it is larger than the sum of its proper divisors (197599).

221025 is a wasteful number, since it uses less digits than its factorization.

221025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 441 (or 436 counting only the distinct ones).

The product of its (nonzero) digits is 40, while the sum is 12.

The square root of 221025 is about 470.1329599167. The cubic root of 221025 is about 60.4617156417.

Adding to 221025 its reverse (520122), we get a palindrome (741147).

The spelling of 221025 in words is "two hundred twenty-one thousand, twenty-five".