28129011 has 4 divisors (see below), whose sum is σ = 37505352. Its totient is φ = 18752672.

The previous prime is 28129007. The next prime is 28129021. The reversal of 28129011 is 11092182.

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 28129011 - 2² = 28129007 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28129021) 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, 4688166 + ... + 4688171.

It is an arithmetic number, because the mean of its divisors is an integer number (9376338).

Almost surely, 2^28129011 is an apocalyptic number.

28129011 is a deficient number, since it is larger than the sum of its proper divisors (9376341).

28129011 is an equidigital number, since it uses as much as digits as its factorization.

28129011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9376340.

The product of its (nonzero) digits is 288, while the sum is 24.

The square root of 28129011 is about 5303.6790061240. The cubic root of 28129011 is about 304.1245558098.

It can be divided in two parts, 281 and 29011, that added together give a palindrome (29292).

The spelling of 28129011 in words is "twenty-eight million, one hundred twenty-nine thousand, eleven".