421656 has 16 divisors (see below), whose sum is σ = 1054200. Its totient is φ = 140544.

The previous prime is 421643. The next prime is 421657. The reversal of 421656 is 656124.

421656 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (24), and also a Moran number because the ratio is a prime number: 17569 = 421656 / (4 + 2 + 1 + 6 + 5 + 6).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421657) 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, 8761 + ... + 8808.

2⁴²¹⁶⁵⁶ is an apocalyptic number.

It is an amenable number.

421656 is an abundant number, since it is smaller than the sum of its proper divisors (632544).

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

421656 is a wasteful number, since it uses less digits than its factorization.

421656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17578 (or 17574 counting only the distinct ones).

The product of its digits is 1440, while the sum is 24.

The square root of 421656 is about 649.3504446753. The cubic root of 421656 is about 74.9870199759.

The spelling of 421656 in words is "four hundred twenty-one thousand, six hundred fifty-six".