28747897 has 4 divisors (see below), whose sum is σ = 29219236. Its totient is φ = 28276560.

The previous prime is 28747843. The next prime is 28747913. The reversal of 28747897 is 79874782.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10523536 + 18224361 = 3244^2 + 4269^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28747897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28747837) 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, 235578 + ... + 235699.

It is an arithmetic number, because the mean of its divisors is an integer number (7304809).

Almost surely, 2^28747897 is an apocalyptic number.

It is an amenable number.

28747897 is a deficient number, since it is larger than the sum of its proper divisors (471339).

28747897 is an equidigital number, since it uses as much as digits as its factorization.

28747897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 471338.

The product of its digits is 1580544, while the sum is 52.

The square root of 28747897 is about 5361.7065380343. The cubic root of 28747897 is about 306.3388140577.

It can be divided in two parts, 287 and 47897, that added together give a palindrome (48184).

The spelling of 28747897 in words is "twenty-eight million, seven hundred forty-seven thousand, eight hundred ninety-seven".