28205145 has 16 divisors (see below), whose sum is σ = 50142720. Its totient is φ = 15042672.

The previous prime is 28205087. The next prime is 28205147. The reversal of 28205145 is 54150282.

It is a happy number.

It is not a de Polignac number, because 28205145 - 2⁷ = 28205017 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (28205147) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 104329 + ... + 104598.

It is an arithmetic number, because the mean of its divisors is an integer number (3133920).

Almost surely, 2^28205145 is an apocalyptic number.

It is an amenable number.

28205145 is a deficient number, since it is larger than the sum of its proper divisors (21937575).

28205145 is a wasteful number, since it uses less digits than its factorization.

28205145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208941 (or 208935 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 27.

The square root of 28205145 is about 5310.8516266226. The cubic root of 28205145 is about 304.3986898767.

The spelling of 28205145 in words is "twenty-eight million, two hundred five thousand, one hundred forty-five".