28965905 has 4 divisors (see below), whose sum is σ = 34759092. Its totient is φ = 23172720.

The previous prime is 28965887. The next prime is 28965913. The reversal of 28965905 is 50956982.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50956982 = 2 ⋅25478491.

It can be written as a sum of positive squares in 2 ways, for example, as 14737921 + 14227984 = 3839^2 + 3772^2 .

It is not a de Polignac number, because 28965905 - 2¹² = 28961809 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2896586 + ... + 2896595.

It is an arithmetic number, because the mean of its divisors is an integer number (8689773).

Almost surely, 2^28965905 is an apocalyptic number.

It is an amenable number.

28965905 is a deficient number, since it is larger than the sum of its proper divisors (5793187).

28965905 is an equidigital number, since it uses as much as digits as its factorization.

28965905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5793186.

The product of its (nonzero) digits is 194400, while the sum is 44.

The square root of 28965905 is about 5381.9982348566. The cubic root of 28965905 is about 307.1112323152. Note that the first 3 decimals are identical.

The spelling of 28965905 in words is "twenty-eight million, nine hundred sixty-five thousand, nine hundred five".