428625531 has 12 divisors (see below), whose sum is σ = 620373000. Its totient is φ = 285174720.

The previous prime is 428625511. The next prime is 428625551. The reversal of 428625531 is 135526824.

428625531 is a `hidden beast` number, since 4 + 28 + 625 + 5 + 3 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (428625511) and next prime (428625551).

It is not a de Polignac number, because 428625531 - 2⁹ = 428625019 is a prime.

It is a super-2 number, since 2×428625531² = 367439691650063922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (428625511) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 43230 + ... + 52211.

It is an arithmetic number, because the mean of its divisors is an integer number (51697750).

Almost surely, 2^428625531 is an apocalyptic number.

428625531 is a deficient number, since it is larger than the sum of its proper divisors (191747469).

428625531 is a wasteful number, since it uses less digits than its factorization.

428625531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95946 (or 95943 counting only the distinct ones).

The product of its digits is 57600, while the sum is 36.

The square root of 428625531 is about 20703.2734368264. The cubic root of 428625531 is about 753.9791656512.

The spelling of 428625531 in words is "four hundred twenty-eight million, six hundred twenty-five thousand, five hundred thirty-one".