28506449 has 4 divisors (see below), whose sum is σ = 29489460. Its totient is φ = 27523440.

The previous prime is 28506437. The next prime is 28506451. The reversal of 28506449 is 94460582.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 94460582 = 2 ⋅47230291.

It can be written as a sum of positive squares in 2 ways, for example, as 23961025 + 4545424 = 4895^2 + 2132^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28506449 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 (28506409) 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, 491462 + ... + 491519.

It is an arithmetic number, because the mean of its divisors is an integer number (7372365).

Almost surely, 2^28506449 is an apocalyptic number.

28506449 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

28506449 is a deficient number, since it is larger than the sum of its proper divisors (983011).

28506449 is an equidigital number, since it uses as much as digits as its factorization.

28506449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 983010.

The product of its (nonzero) digits is 69120, while the sum is 38.

The square root of 28506449 is about 5339.1430960408. The cubic root of 28506449 is about 305.4787750564.

The spelling of 28506449 in words is "twenty-eight million, five hundred six thousand, four hundred forty-nine".