28684520 has 16 divisors (see below), whose sum is σ = 64540260. Its totient is φ = 11473792.

The previous prime is 28684511. The next prime is 28684529. The reversal of 28684520 is 2548682.

It is an interprime number because it is at equal distance from previous prime (28684511) and next prime (28684529).

It can be written as a sum of positive squares in 2 ways, for example, as 27899524 + 784996 = 5282^2 + 886^2 .

It is not an unprimeable number, because it can be changed into a prime (28684529) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 358517 + ... + 358596.

Almost surely, 2^28684520 is an apocalyptic number.

28684520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28684520 is an abundant number, since it is smaller than the sum of its proper divisors (35855740).

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

28684520 is a wasteful number, since it uses less digits than its factorization.

28684520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 717124 (or 717120 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 35.

The square root of 28684520 is about 5355.7931252056. The cubic root of 28684520 is about 306.1135324230.

The spelling of 28684520 in words is "twenty-eight million, six hundred eighty-four thousand, five hundred twenty".