420423505 has 4 divisors (see below), whose sum is σ = 504508212. Its totient is φ = 336338800.

The previous prime is 420423503. The next prime is 420423533. The reversal of 420423505 is 505324024.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 281937681 + 138485824 = 16791^2 + 11768^2 .

It is not a de Polignac number, because 420423505 - 2¹ = 420423503 is a prime.

It is a super-3 number, since 3×420423505³ (a number of 27 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 420423505.

It is not an unprimeable number, because it can be changed into a prime (420423503) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42042346 + ... + 42042355.

It is an arithmetic number, because the mean of its divisors is an integer number (126127053).

Almost surely, 2^420423505 is an apocalyptic number.

It is an amenable number.

420423505 is a deficient number, since it is larger than the sum of its proper divisors (84084707).

420423505 is an equidigital number, since it uses as much as digits as its factorization.

420423505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84084706.

The product of its (nonzero) digits is 4800, while the sum is 25.

The square root of 420423505 is about 20504.2313925687. The cubic root of 420423505 is about 749.1388664586.

Adding to 420423505 its reverse (505324024), we get a palindrome (925747529).

The spelling of 420423505 in words is "four hundred twenty million, four hundred twenty-three thousand, five hundred five".