4220421 has 4 divisors (see below), whose sum is σ = 5627232. Its totient is φ = 2813612.

The previous prime is 4220393. The next prime is 4220423. The reversal of 4220421 is 1240224.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 4220421 - 2⁶ = 4220357 is a prime.

It is a D-number.

4220421 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 4220421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4220423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 703401 + ... + 703406.

It is an arithmetic number, because the mean of its divisors is an integer number (1406808).

Almost surely, 2^4220421 is an apocalyptic number.

It is an amenable number.

4220421 is a deficient number, since it is larger than the sum of its proper divisors (1406811).

4220421 is a wasteful number, since it uses less digits than its factorization.

4220421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1406810.

The product of its (nonzero) digits is 128, while the sum is 15.

The square root of 4220421 is about 2054.3663256586. The cubic root of 4220421 is about 161.6039326274.

Adding to 4220421 its reverse (1240224), we get a palindrome (5460645).

The spelling of 4220421 in words is "four million, two hundred twenty thousand, four hundred twenty-one".