28308953 has 4 divisors (see below), whose sum is σ = 28355748. Its totient is φ = 28262160.

The previous prime is 28308947. The next prime is 28308971. The reversal of 28308953 is 35980382.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 35980382 = 2 ⋅17990191.

It can be written as a sum of positive squares in 2 ways, for example, as 8479744 + 19829209 = 2912^2 + 4453^2 .

It is a cyclic number.

It is not a de Polignac number, because 28308953 - 2⁴ = 28308937 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28308913) 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, 22478 + ... + 23703.

It is an arithmetic number, because the mean of its divisors is an integer number (7088937).

Almost surely, 2^28308953 is an apocalyptic number.

It is an amenable number.

28308953 is a deficient number, since it is larger than the sum of its proper divisors (46795).

28308953 is an equidigital number, since it uses as much as digits as its factorization.

28308953 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46794.

The product of its (nonzero) digits is 51840, while the sum is 38.

The square root of 28308953 is about 5320.6158478131. The cubic root of 28308953 is about 304.7716753955.

The spelling of 28308953 in words is "twenty-eight million, three hundred eight thousand, nine hundred fifty-three".