4020421 has 8 divisors (see below), whose sum is σ = 4230144. Its totient is φ = 3815760.

The previous prime is 4020409. The next prime is 4020431. The reversal of 4020421 is 1240204.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 4020421 - 2⁷ = 4020293 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 (4020431) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 420 + ... + 2866.

It is an arithmetic number, because the mean of its divisors is an integer number (528768).

Almost surely, 2^4020421 is an apocalyptic number.

It is an amenable number.

4020421 is a deficient number, since it is larger than the sum of its proper divisors (209723).

4020421 is a wasteful number, since it uses less digits than its factorization.

4020421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2531.

The product of its (nonzero) digits is 64, while the sum is 13.

The square root of 4020421 is about 2005.0987506854. The cubic root of 4020421 is about 159.0097827664.

Adding to 4020421 its reverse (1240204), we get a palindrome (5260625).

The spelling of 4020421 in words is "four million, twenty thousand, four hundred twenty-one".