28247897 has 4 divisors (see below), whose sum is σ = 29909556. Its totient is φ = 26586240.

The previous prime is 28247881. The next prime is 28247899. The reversal of 28247897 is 79874282.

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: 79874282 = 2 ⋅39937141.

It can be written as a sum of positive squares in 2 ways, for example, as 13278736 + 14969161 = 3644^2 + 3869^2 .

It is a cyclic number.

It is not a de Polignac number, because 28247897 - 2⁴ = 28247881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28247899) 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, 830804 + ... + 830837.

It is an arithmetic number, because the mean of its divisors is an integer number (7477389).

Almost surely, 2^28247897 is an apocalyptic number.

It is an amenable number.

28247897 is a deficient number, since it is larger than the sum of its proper divisors (1661659).

28247897 is a wasteful number, since it uses less digits than its factorization.

28247897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1661658.

The product of its digits is 451584, while the sum is 47.

The square root of 28247897 is about 5314.8750690868. The cubic root of 28247897 is about 304.5524098589.

The spelling of 28247897 in words is "twenty-eight million, two hundred forty-seven thousand, eight hundred ninety-seven".