28009671 has 4 divisors (see below), whose sum is σ = 37346232. Its totient is φ = 18673112.

The previous prime is 28009669. The next prime is 28009721. The reversal of 28009671 is 17690082.

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 28009671 - 2¹ = 28009669 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28009661) 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, 4668276 + ... + 4668281.

It is an arithmetic number, because the mean of its divisors is an integer number (9336558).

Almost surely, 2^28009671 is an apocalyptic number.

28009671 is a deficient number, since it is larger than the sum of its proper divisors (9336561).

28009671 is an equidigital number, since it uses as much as digits as its factorization.

28009671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9336560.

The product of its (nonzero) digits is 6048, while the sum is 33.

The square root of 28009671 is about 5292.4163668404. The cubic root of 28009671 is about 303.6938537013.

It can be divided in two parts, 28009 and 671, that added together give a triangular number (28680 = T₂₃₉).

The spelling of 28009671 in words is "twenty-eight million, nine thousand, six hundred seventy-one".