28663447 has 4 divisors (see below), whose sum is σ = 28777896. Its totient is φ = 28549000.

The previous prime is 28663433. The next prime is 28663463. The reversal of 28663447 is 74436682.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 74436682 = 2 ⋅37218341.

It is a cyclic number.

It is not a de Polignac number, because 28663447 - 2⁷ = 28663319 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28663487) 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, 56848 + ... + 57349.

It is an arithmetic number, because the mean of its divisors is an integer number (7194474).

Almost surely, 2^28663447 is an apocalyptic number.

28663447 is a deficient number, since it is larger than the sum of its proper divisors (114449).

28663447 is a wasteful number, since it uses less digits than its factorization.

28663447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114448.

The product of its digits is 193536, while the sum is 40.

The square root of 28663447 is about 5353.8254547566. The cubic root of 28663447 is about 306.0385522504.

The spelling of 28663447 in words is "twenty-eight million, six hundred sixty-three thousand, four hundred forty-seven".