428521806 has 32 divisors (see below), whose sum is σ = 985111200. Its totient is φ = 137914560.

The previous prime is 428521783. The next prime is 428521817. The reversal of 428521806 is 608125824.

428521806 is a `hidden beast` number, since 428 + 52 + 180 + 6 = 666.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 135255 + ... + 138386.

It is an arithmetic number, because the mean of its divisors is an integer number (30784725).

Almost surely, 2^428521806 is an apocalyptic number.

428521806 is an abundant number, since it is smaller than the sum of its proper divisors (556589394).

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

428521806 is a wasteful number, since it uses less digits than its factorization.

428521806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 273681 (or 273675 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

The square root of 428521806 is about 20700.7682466135. The cubic root of 428521806 is about 753.9183411532.

The spelling of 428521806 in words is "four hundred twenty-eight million, five hundred twenty-one thousand, eight hundred six".