28161719 has 4 divisors (see below), whose sum is σ = 28452144. Its totient is φ = 27871296.

The previous prime is 28161701. The next prime is 28161767. The reversal of 28161719 is 91716182.

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 28161719 - 2¹⁶ = 28096183 is a prime.

It is a super-2 number, since 2×28161719² = 1586164834069922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28161769) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 145067 + ... + 145260.

It is an arithmetic number, because the mean of its divisors is an integer number (7113036).

Almost surely, 2^28161719 is an apocalyptic number.

28161719 is a deficient number, since it is larger than the sum of its proper divisors (290425).

28161719 is an equidigital number, since it uses as much as digits as its factorization.

28161719 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 290424.

The product of its digits is 6048, while the sum is 35.

The square root of 28161719 is about 5306.7616302223. The cubic root of 28161719 is about 304.2423873365.

The spelling of 28161719 in words is "twenty-eight million, one hundred sixty-one thousand, seven hundred nineteen".