28978841 has 4 divisors (see below), whose sum is σ = 29685684. Its totient is φ = 28272000.

The previous prime is 28978823. The next prime is 28978867. The reversal of 28978841 is 14887982.

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 4426816 + 24552025 = 2104^2 + 4955^2 .

It is a cyclic number.

It is not a de Polignac number, because 28978841 - 2¹⁸ = 28716697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28978241) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 353360 + ... + 353441.

It is an arithmetic number, because the mean of its divisors is an integer number (7421421).

Almost surely, 2^28978841 is an apocalyptic number.

It is an amenable number.

28978841 is a deficient number, since it is larger than the sum of its proper divisors (706843).

28978841 is an equidigital number, since it uses as much as digits as its factorization.

28978841 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 706842.

The product of its digits is 258048, while the sum is 47.

The square root of 28978841 is about 5383.1998848269. The cubic root of 28978841 is about 307.1569435245.

The spelling of 28978841 in words is "twenty-eight million, nine hundred seventy-eight thousand, eight hundred forty-one".