428444640 has 240 divisors, whose sum is σ = 1629004608. Its totient is φ = 105421824.

The previous prime is 428444617. The next prime is 428444651. The reversal of 428444640 is 46444824.

428444640 is a `hidden beast` number, since 4 + 2 + 8 + 4 + 4 + 4 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 428444595 and 428444604.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 167209 + ... + 169751.

Almost surely, 2^428444640 is an apocalyptic number.

428444640 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 428444640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (814502304).

428444640 is an abundant number, since it is smaller than the sum of its proper divisors (1200559968).

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

428444640 is a wasteful number, since it uses less digits than its factorization.

428444640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2583 (or 2566 counting only the distinct ones).

The product of its (nonzero) digits is 98304, while the sum is 36.

The square root of 428444640 is about 20698.9043188281. The cubic root of 428444640 is about 753.8730845258.

The spelling of 428444640 in words is "four hundred twenty-eight million, four hundred forty-four thousand, six hundred forty".