4221420 has 144 divisors (see below), whose sum is σ = 14864640. Its totient is φ = 874368.

The previous prime is 4221419. The next prime is 4221421. The reversal of 4221420 is 241224.

It is an interprime number because it is at equal distance from previous prime (4221419) and next prime (4221421).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 4221420.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4221421) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 183529 + ... + 183551.

Almost surely, 2^4221420 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 4221420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7432320).

4221420 is an abundant number, since it is smaller than the sum of its proper divisors (10643220).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

4221420 is a wasteful number, since it uses less digits than its factorization.

4221420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84 (or 59 counting only the distinct ones).

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

The square root of 4221420 is about 2054.6094519397. The cubic root of 4221420 is about 161.6166825081.

Adding to 4221420 its reverse (241224), we get a palindrome (4462644).

The spelling of 4221420 in words is "four million, two hundred twenty-one thousand, four hundred twenty".