428905521 has 48 divisors (see below), whose sum is σ = 704987712. Its totient is φ = 248976000.

The previous prime is 428905511. The next prime is 428905523. The reversal of 428905521 is 125509824.

428905521 is a `hidden beast` number, since 42 + 8 + 90 + 5 + 521 = 666.

It is not a de Polignac number, because 428905521 - 2¹⁸ = 428643377 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (428905523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 224671 + ... + 226571.

It is an arithmetic number, because the mean of its divisors is an integer number (14687244).

Almost surely, 2^428905521 is an apocalyptic number.

It is an amenable number.

428905521 is a deficient number, since it is larger than the sum of its proper divisors (276082191).

428905521 is a wasteful number, since it uses less digits than its factorization.

428905521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2014 (or 2011 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

The square root of 428905521 is about 20710.0343070696. The cubic root of 428905521 is about 754.1433032345.

The spelling of 428905521 in words is "four hundred twenty-eight million, nine hundred five thousand, five hundred twenty-one".