28178413 has 4 divisors (see below), whose sum is σ = 28341468. Its totient is φ = 28015360.

The previous prime is 28178389. The next prime is 28178419. The reversal of 28178413 is 31487182.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 23843689 + 4334724 = 4883^2 + 2082^2 .

It is a cyclic number.

It is not a de Polignac number, because 28178413 - 2¹³ = 28170221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28178419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 81268 + ... + 81613.

It is an arithmetic number, because the mean of its divisors is an integer number (7085367).

Almost surely, 2^28178413 is an apocalyptic number.

It is an amenable number.

28178413 is a deficient number, since it is larger than the sum of its proper divisors (163055).

28178413 is a wasteful number, since it uses less digits than its factorization.

28178413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163054.

The product of its digits is 10752, while the sum is 34.

The square root of 28178413 is about 5308.3342961799. The cubic root of 28178413 is about 304.3024927956.

The spelling of 28178413 in words is "twenty-eight million, one hundred seventy-eight thousand, four hundred thirteen".