420709 has 4 divisors (see below), whose sum is σ = 422604. Its totient is φ = 418816.

The previous prime is 420691. The next prime is 420731. The reversal of 420709 is 907024.

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 220900 + 199809 = 470^2 + 447^2 .

It is a cyclic number.

It is not a de Polignac number, because 420709 - 2⁵ = 420677 is a prime.

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 420709.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (420769) 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, 562 + ... + 1075.

It is an arithmetic number, because the mean of its divisors is an integer number (105651).

2⁴²⁰⁷⁰⁹ is an apocalyptic number.

It is an amenable number.

420709 is a deficient number, since it is larger than the sum of its proper divisors (1895).

420709 is a wasteful number, since it uses less digits than its factorization.

420709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1894.

The product of its (nonzero) digits is 504, while the sum is 22.

The square root of 420709 is about 648.6208445618. The cubic root of 420709 is about 74.9308399485.

The spelling of 420709 in words is "four hundred twenty thousand, seven hundred nine".