28605919 has 4 divisors (see below), whose sum is σ = 29592360. Its totient is φ = 27619480.

The previous prime is 28605911. The next prime is 28605937. The reversal of 28605919 is 91950682.

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

It is a cyclic number.

It is not a de Polignac number, because 28605919 - 2³ = 28605911 is a prime.

It is a super-2 number, since 2×28605919² = 1636597203669122, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28605911) 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, 493177 + ... + 493234.

It is an arithmetic number, because the mean of its divisors is an integer number (7398090).

Almost surely, 2^28605919 is an apocalyptic number.

28605919 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

28605919 is a deficient number, since it is larger than the sum of its proper divisors (986441).

28605919 is an equidigital number, since it uses as much as digits as its factorization.

28605919 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 986440.

The product of its (nonzero) digits is 38880, while the sum is 40.

The square root of 28605919 is about 5348.4501493423. The cubic root of 28605919 is about 305.8336736891.

The spelling of 28605919 in words is "twenty-eight million, six hundred five thousand, nine hundred nineteen".