420789 has 4 divisors (see below), whose sum is σ = 561056. Its totient is φ = 280524.

The previous prime is 420781. The next prime is 420799. The reversal of 420789 is 987024.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 420789 - 2³ = 420781 is a prime.

It is a D-number.

It is a Duffinian number.

420789 is a lucky number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 420789.

It is not an unprimeable number, because it can be changed into a prime (420781) 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, 70129 + ... + 70134.

It is an arithmetic number, because the mean of its divisors is an integer number (140264).

2⁴²⁰⁷⁸⁹ is an apocalyptic number.

It is an amenable number.

420789 is a deficient number, since it is larger than the sum of its proper divisors (140267).

420789 is a wasteful number, since it uses less digits than its factorization.

420789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140266.

The product of its (nonzero) digits is 4032, while the sum is 30.

The square root of 420789 is about 648.6825109404. The cubic root of 420789 is about 74.9355891435.

The spelling of 420789 in words is "four hundred twenty thousand, seven hundred eighty-nine".