420531 has 4 divisors (see below), whose sum is σ = 560712. Its totient is φ = 280352.

The previous prime is 420521. The next prime is 420551. The reversal of 420531 is 135024.

420531 is nontrivially palindromic in base 2.

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

It is a cyclic number.

It is not a de Polignac number, because 420531 - 2⁵ = 420499 is a prime.

It is a super-2 number, since 2×420531² = 353692643922, which contains 22 as substring.

It is a D-number.

It is a self number, because there is not a number n which added to its sum of digits gives 420531.

It is not an unprimeable number, because it can be changed into a prime (420521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 70086 + ... + 70091.

It is an arithmetic number, because the mean of its divisors is an integer number (140178).

2⁴²⁰⁵³¹ is an apocalyptic number.

420531 is a deficient number, since it is larger than the sum of its proper divisors (140181).

420531 is a wasteful number, since it uses less digits than its factorization.

420531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140180.

The product of its (nonzero) digits is 120, while the sum is 15.

The square root of 420531 is about 648.4836158300. The cubic root of 420531 is about 74.9202708290.

Adding to 420531 its reverse (135024), we get a palindrome (555555).

The spelling of 420531 in words is "four hundred twenty thousand, five hundred thirty-one".