28281011 has 4 divisors (see below), whose sum is σ = 30852024. Its totient is φ = 25710000.

The previous prime is 28280999. The next prime is 28281037. The reversal of 28281011 is 11018282.

It is a happy number.

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 28281011 - 2⁶ = 28280947 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28281041) 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, 1285490 + ... + 1285511.

It is an arithmetic number, because the mean of its divisors is an integer number (7713006).

Almost surely, 2^28281011 is an apocalyptic number.

28281011 is a deficient number, since it is larger than the sum of its proper divisors (2571013).

28281011 is a wasteful number, since it uses less digits than its factorization.

28281011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2571012.

The product of its (nonzero) digits is 256, while the sum is 23.

The square root of 28281011 is about 5317.9893756945. The cubic root of 28281011 is about 304.6713686888.

Adding to 28281011 its reverse (11018282), we get a palindrome (39299293).

The spelling of 28281011 in words is "twenty-eight million, two hundred eighty-one thousand, eleven".