421056 has 84 divisors (see below), whose sum is σ = 1307592. Its totient is φ = 129024.

The previous prime is 421049. The next prime is 421079. The reversal of 421056 is 650124.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

421056 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9771 + ... + 9813.

2⁴²¹⁰⁵⁶ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 421056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (653796).

421056 is an abundant number, since it is smaller than the sum of its proper divisors (886536).

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

421056 is a wasteful number, since it uses less digits than its factorization.

421056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78 (or 65 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 421056 is about 648.8882800606. Note that the first 3 decimals coincide. The cubic root of 421056 is about 74.9514352263.

The spelling of 421056 in words is "four hundred twenty-one thousand, fifty-six".