420638 has 4 divisors (see below), whose sum is σ = 630960. Its totient is φ = 210318.

The previous prime is 420613. The next prime is 420671. The reversal of 420638 is 836024.

It is a happy number.

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

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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, 105158 + ... + 105161.

It is an arithmetic number, because the mean of its divisors is an integer number (157740).

2⁴²⁰⁶³⁸ is an apocalyptic number.

420638 is a deficient number, since it is larger than the sum of its proper divisors (210322).

420638 is a wasteful number, since it uses less digits than its factorization.

420638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210321.

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 420638 is about 648.5661107397. The cubic root of 420638 is about 74.9266245336.

The spelling of 420638 in words is "four hundred twenty thousand, six hundred thirty-eight".