28012549 has 4 divisors (see below), whose sum is σ = 29660364. Its totient is φ = 26364736.

The previous prime is 28012547. The next prime is 28012559. The reversal of 28012549 is 94521082.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 94521082 = 2 ⋅47260541.

It can be written as a sum of positive squares in 2 ways, for example, as 7924225 + 20088324 = 2815^2 + 4482^2 .

It is a cyclic number.

It is not a de Polignac number, because 28012549 - 2¹ = 28012547 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28012549.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28012541) 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 3 ways as a sum of consecutive naturals, for example, 823882 + ... + 823915.

It is an arithmetic number, because the mean of its divisors is an integer number (7415091).

Almost surely, 2^28012549 is an apocalyptic number.

It is an amenable number.

28012549 is a deficient number, since it is larger than the sum of its proper divisors (1647815).

28012549 is a wasteful number, since it uses less digits than its factorization.

28012549 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1647814.

The product of its (nonzero) digits is 5760, while the sum is 31.

The square root of 28012549 is about 5292.6882583428. The cubic root of 28012549 is about 303.7042548824.

It can be divided in two parts, 28012 and 549, that added together give a 4-th power (28561 = 13⁴).

The spelling of 28012549 in words is "twenty-eight million, twelve thousand, five hundred forty-nine".