28129001 has 4 divisors (see below), whose sum is σ = 28203600. Its totient is φ = 28054404.

The previous prime is 28128973. The next prime is 28129007. The reversal of 28129001 is 10092182.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 28129001 - 2⁶ = 28128937 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28129007) 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, 36731 + ... + 37488.

It is an arithmetic number, because the mean of its divisors is an integer number (7050900).

Almost surely, 2^28129001 is an apocalyptic number.

It is an amenable number.

28129001 is a deficient number, since it is larger than the sum of its proper divisors (74599).

28129001 is an equidigital number, since it uses as much as digits as its factorization.

28129001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74598.

The product of its (nonzero) digits is 288, while the sum is 23.

The square root of 28129001 is about 5303.6780633821. The cubic root of 28129001 is about 304.1245197706.

The spelling of 28129001 in words is "twenty-eight million, one hundred twenty-nine thousand, one".