28821079 has 4 divisors (see below), whose sum is σ = 32938384. Its totient is φ = 24703776.

The previous prime is 28821077. The next prime is 28821109. The reversal of 28821079 is 97012882.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 97012882 = 2 ⋅48506441.

It is a cyclic number.

It is not a de Polignac number, because 28821079 - 2¹ = 28821077 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 (28821071) 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, 2058642 + ... + 2058655.

It is an arithmetic number, because the mean of its divisors is an integer number (8234596).

Almost surely, 2^28821079 is an apocalyptic number.

28821079 is a deficient number, since it is larger than the sum of its proper divisors (4117305).

28821079 is an equidigital number, since it uses as much as digits as its factorization.

28821079 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4117304.

The product of its (nonzero) digits is 16128, while the sum is 37.

The square root of 28821079 is about 5368.5267066487. The cubic root of 28821079 is about 306.5985372966.

The spelling of 28821079 in words is "twenty-eight million, eight hundred twenty-one thousand, seventy-nine".