28251361 has 4 divisors (see below), whose sum is σ = 28265152. Its totient is φ = 28237572.

The previous prime is 28251343. The next prime is 28251373. The reversal of 28251361 is 16315282.

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, and also an emirpimes, since its reverse is a distinct semiprime: 16315282 = 2 ⋅8157641.

It is a cyclic number.

It is not a de Polignac number, because 28251361 - 2¹⁷ = 28120289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28251341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3141 + ... + 8146.

It is an arithmetic number, because the mean of its divisors is an integer number (7066288).

Almost surely, 2^28251361 is an apocalyptic number.

It is an amenable number.

28251361 is a deficient number, since it is larger than the sum of its proper divisors (13791).

28251361 is a wasteful number, since it uses less digits than its factorization.

28251361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13790.

The product of its digits is 2880, while the sum is 28.

The square root of 28251361 is about 5315.2009369355. The cubic root of 28251361 is about 304.5648582951.

It can be divided in two parts, 2825 and 1361, that added together give a triangular number (4186 = T₉₁).

The spelling of 28251361 in words is "twenty-eight million, two hundred fifty-one thousand, three hundred sixty-one".