28107947 has 4 divisors (see below), whose sum is σ = 32123376. Its totient is φ = 24092520.

The previous prime is 28107929. The next prime is 28107971. The reversal of 28107947 is 74970182.

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

It is a cyclic number.

It is not a de Polignac number, because 28107947 - 2¹⁴ = 28091563 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28107947.

It is not an unprimeable number, because it can be changed into a prime (28103947) 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, 2007704 + ... + 2007717.

It is an arithmetic number, because the mean of its divisors is an integer number (8030844).

Almost surely, 2^28107947 is an apocalyptic number.

28107947 is a deficient number, since it is larger than the sum of its proper divisors (4015429).

28107947 is an equidigital number, since it uses as much as digits as its factorization.

28107947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4015428.

The product of its (nonzero) digits is 28224, while the sum is 38.

The square root of 28107947 is about 5301.6928428569. The cubic root of 28107947 is about 304.0486237725.

The spelling of 28107947 in words is "twenty-eight million, one hundred seven thousand, nine hundred forty-seven".