820431 has 6 divisors (see below), whose sum is σ = 1185080. Its totient is φ = 546948.

The previous prime is 820429. The next prime is 820441. The reversal of 820431 is 134028.

It is a happy number.

820431 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 820431 - 2¹ = 820429 is a prime.

It is a super-2 number, since 2×820431² = 1346214051522, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820411) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 45571 + ... + 45588.

2⁸²⁰⁴³¹ is an apocalyptic number.

820431 is a deficient number, since it is larger than the sum of its proper divisors (364649).

820431 is a wasteful number, since it uses less digits than its factorization.

820431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91165 (or 91162 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 820431 is about 905.7764624895. The cubic root of 820431 is about 93.6154122111.

Adding to 820431 its reverse (134028), we get a palindrome (954459).

The spelling of 820431 in words is "eight hundred twenty thousand, four hundred thirty-one".