28440719 has 4 divisors (see below), whose sum is σ = 29677296. Its totient is φ = 27204144.

The previous prime is 28440689. The next prime is 28440721. The reversal of 28440719 is 91704482.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 91704482 = 2 ⋅45852241.

It is a cyclic number.

It is not a de Polignac number, because 28440719 - 2¹² = 28436623 is a prime.

It is a super-2 number, since 2×28440719² = 1617748994473922, 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 (28440749) 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, 618254 + ... + 618299.

It is an arithmetic number, because the mean of its divisors is an integer number (7419324).

Almost surely, 2^28440719 is an apocalyptic number.

28440719 is a deficient number, since it is larger than the sum of its proper divisors (1236577).

28440719 is a wasteful number, since it uses less digits than its factorization.

28440719 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1236576.

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 28440719 is about 5332.9840614800. The cubic root of 28440719 is about 305.2438039866.

The spelling of 28440719 in words is "twenty-eight million, four hundred forty thousand, seven hundred nineteen".