421025221 has 4 divisors (see below), whose sum is σ = 422274892. Its totient is φ = 419775552.

The previous prime is 421025197. The next prime is 421025261. The reversal of 421025221 is 122520124.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 59074596 + 361950625 = 7686^2 + 19025^2 .

It is a cyclic number.

It is not a de Polignac number, because 421025221 - 2²⁵ = 387470789 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421025261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 624330 + ... + 625003.

It is an arithmetic number, because the mean of its divisors is an integer number (105568723).

Almost surely, 2^421025221 is an apocalyptic number.

It is an amenable number.

421025221 is a deficient number, since it is larger than the sum of its proper divisors (1249671).

421025221 is a wasteful number, since it uses less digits than its factorization.

421025221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1249670.

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

The square root of 421025221 is about 20518.8991176427. The cubic root of 421025221 is about 749.4960887664.

Adding to 421025221 its reverse (122520124), we get a palindrome (543545345).

The spelling of 421025221 in words is "four hundred twenty-one million, twenty-five thousand, two hundred twenty-one".