420021823 has 16 divisors (see below), whose sum is σ = 457179520. Its totient is φ = 383582304.

The previous prime is 420021803. The next prime is 420021827. The reversal of 420021823 is 328120024.

It is a cyclic number.

It is not a de Polignac number, because 420021823 - 2¹³ = 420013631 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 420021794 and 420021803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (420021827) 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 15 ways as a sum of consecutive naturals, for example, 802840 + ... + 803362.

It is an arithmetic number, because the mean of its divisors is an integer number (28573720).

Almost surely, 2^420021823 is an apocalyptic number.

420021823 is a deficient number, since it is larger than the sum of its proper divisors (37157697).

420021823 is a wasteful number, since it uses less digits than its factorization.

420021823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1078.

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 420021823 is about 20494.4339516855. The cubic root of 420021823 is about 748.9002091053.

Adding to 420021823 its reverse (328120024), we get a palindrome (748141847).

The spelling of 420021823 in words is "four hundred twenty million, twenty-one thousand, eight hundred twenty-three".