420806 has 4 divisors (see below), whose sum is σ = 631212. Its totient is φ = 210402.

The previous prime is 420803. The next prime is 420809. The reversal of 420806 is 608024.

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

It is an interprime number because it is at equal distance from previous prime (420803) and next prime (420809).

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (420803) 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 as a sum of consecutive naturals, namely, 105200 + ... + 105203.

It is an arithmetic number, because the mean of its divisors is an integer number (157803).

2⁴²⁰⁸⁰⁶ is an apocalyptic number.

420806 is a deficient number, since it is larger than the sum of its proper divisors (210406).

420806 is a wasteful number, since it uses less digits than its factorization.

420806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210405.

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 420806 is about 648.6956142907. The cubic root of 420806 is about 74.9365982699.

The spelling of 420806 in words is "four hundred twenty thousand, eight hundred six".