424021221 has 48 divisors (see below), whose sum is σ = 694228080. Its totient is φ = 247587840.

The previous prime is 424021219. The next prime is 424021229. The reversal of 424021221 is 122120424.

424021221 is a `hidden beast` number, since 42 + 402 + 1 + 221 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 62489025 + 361532196 = 7905^2 + 19014^2 .

It is not a de Polignac number, because 424021221 - 2¹ = 424021219 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 424021194 and 424021203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (424021229) 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 47 ways as a sum of consecutive naturals, for example, 176295 + ... + 178683.

It is an arithmetic number, because the mean of its divisors is an integer number (14463085).

Almost surely, 2^424021221 is an apocalyptic number.

424021221 is a gapful number since it is divisible by the number (41) formed by its first and last digit.

It is an amenable number.

424021221 is a deficient number, since it is larger than the sum of its proper divisors (270206859).

424021221 is a wasteful number, since it uses less digits than its factorization.

424021221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2486 (or 2483 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 424021221 is about 20591.7755669588. The cubic root of 424021221 is about 751.2696839905.

Adding to 424021221 its reverse (122120424), we get a palindrome (546141645).

The spelling of 424021221 in words is "four hundred twenty-four million, twenty-one thousand, two hundred twenty-one".