421504531 has 32 divisors (see below), whose sum is σ = 530150400. Its totient is φ = 326954880.

The previous prime is 421504519. The next prime is 421504541. The reversal of 421504531 is 135405124.

It is a happy number.

It is not a de Polignac number, because 421504531 - 2⁹ = 421504019 is a prime.

It is a super-2 number, since 2×421504531² = 355332139307059922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 421504496 and 421504505.

It is not an unprimeable number, because it can be changed into a prime (421504541) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 396741 + ... + 397801.

It is an arithmetic number, because the mean of its divisors is an integer number (16567200).

Almost surely, 2^421504531 is an apocalyptic number.

421504531 is a deficient number, since it is larger than the sum of its proper divisors (108645869).

421504531 is a wasteful number, since it uses less digits than its factorization.

421504531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1219.

The product of its (nonzero) digits is 2400, while the sum is 25.

The square root of 421504531 is about 20530.5755155573. The cubic root of 421504531 is about 749.7803985213.

Adding to 421504531 its reverse (135405124), we get a palindrome (556909655).

The spelling of 421504531 in words is "four hundred twenty-one million, five hundred four thousand, five hundred thirty-one".