28281667 has 4 divisors (see below), whose sum is σ = 28297440. Its totient is φ = 28265896.

The previous prime is 28281629. The next prime is 28281679. The reversal of 28281667 is 76618282.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28281667 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28281767) 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, 4792 + ... + 8917.

It is an arithmetic number, because the mean of its divisors is an integer number (7074360).

Almost surely, 2^28281667 is an apocalyptic number.

28281667 is a deficient number, since it is larger than the sum of its proper divisors (15773).

28281667 is a wasteful number, since it uses less digits than its factorization.

28281667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15772.

The product of its digits is 64512, while the sum is 40.

The square root of 28281667 is about 5318.0510527824. The cubic root of 28281667 is about 304.6737243669.

The spelling of 28281667 in words is "twenty-eight million, two hundred eighty-one thousand, six hundred sixty-seven".