420721056 has 144 divisors (see below), whose sum is σ = 1395576000. Its totient is φ = 120177792.

The previous prime is 420721031. The next prime is 420721061. The reversal of 420721056 is 650127024.

It is a tau number, because it is divible by the number of its divisors (144).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 96655 + ... + 100913.

It is an arithmetic number, because the mean of its divisors is an integer number (9691500).

Almost surely, 2^420721056 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 420721056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (697788000).

420721056 is an abundant number, since it is smaller than the sum of its proper divisors (974854944).

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

420721056 is a wasteful number, since it uses less digits than its factorization.

420721056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4296 (or 4271 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

The square root of 420721056 is about 20511.4859529972. The cubic root of 420721056 is about 749.3155569069.

The spelling of 420721056 in words is "four hundred twenty million, seven hundred twenty-one thousand, fifty-six".