420644 has 24 divisors (see below), whose sum is σ = 856128. Its totient is φ = 177120.

The previous prime is 420613. The next prime is 420671. The reversal of 420644 is 446024.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2234 + ... + 2414.

It is an arithmetic number, because the mean of its divisors is an integer number (35672).

2⁴²⁰⁶⁴⁴ is an apocalyptic number.

It is an amenable number.

420644 is an abundant number, since it is smaller than the sum of its proper divisors (435484).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

420644 is a wasteful number, since it uses less digits than its factorization.

420644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 275 (or 273 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 420644 is about 648.5707363118. The cubic root of 420644 is about 74.9269807842.

Adding to 420644 its reverse (446024), we get a palindrome (866668).

It can be divided in two parts, 420 and 644, that multiplied together give a triangular number (270480 = T₇₃₅).

The spelling of 420644 in words is "four hundred twenty thousand, six hundred forty-four".