420434021 has 24 divisors (see below), whose sum is σ = 518942976. Its totient is φ = 333515520.

The previous prime is 420434011. The next prime is 420434041. The reversal of 420434021 is 120434024.

It is not a de Polignac number, because 420434021 - 2¹⁴ = 420417637 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 420433984 and 420434002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (420434011) 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 23 ways as a sum of consecutive naturals, for example, 121700 + ... + 125106.

It is an arithmetic number, because the mean of its divisors is an integer number (21622624).

Almost surely, 2^420434021 is an apocalyptic number.

It is an amenable number.

420434021 is a deficient number, since it is larger than the sum of its proper divisors (98508955).

420434021 is a wasteful number, since it uses less digits than its factorization.

420434021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3509 (or 3492 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 420434021 is about 20504.4878258395. The cubic root of 420434021 is about 749.1451124451.

Adding to 420434021 its reverse (120434024), we get a palindrome (540868045).

It can be divided in two parts, 42043 and 4021, that added together give a palindrome (46064).

The spelling of 420434021 in words is "four hundred twenty million, four hundred thirty-four thousand, twenty-one".