28693979 has 4 divisors (see below), whose sum is σ = 28746984. Its totient is φ = 28640976.

The previous prime is 28693957. The next prime is 28693993. The reversal of 28693979 is 97939682.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 97939682 = 2 ⋅48969841.

It is a cyclic number.

It is not a de Polignac number, because 28693979 - 2²⁰ = 27645403 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 28693979.

It is not an unprimeable number, because it can be changed into a prime (28693919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25682 + ... + 26775.

It is an arithmetic number, because the mean of its divisors is an integer number (7186746).

Almost surely, 2^28693979 is an apocalyptic number.

28693979 is a deficient number, since it is larger than the sum of its proper divisors (53005).

28693979 is an equidigital number, since it uses as much as digits as its factorization.

28693979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53004.

The product of its digits is 1469664, while the sum is 53.

The square root of 28693979 is about 5356.6761149056. The cubic root of 28693979 is about 306.1471766985.

The spelling of 28693979 in words is "twenty-eight million, six hundred ninety-three thousand, nine hundred seventy-nine".