28709423 has 6 divisors (see below), whose sum is σ = 29394504. Its totient is φ = 28039956.

The previous prime is 28709419. The next prime is 28709453. The reversal of 28709423 is 32490782.

It is not a de Polignac number, because 28709423 - 2² = 28709419 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28709453) 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 5 ways as a sum of consecutive naturals, for example, 5915 + ... + 9612.

It is an arithmetic number, because the mean of its divisors is an integer number (4899084).

Almost surely, 2^28709423 is an apocalyptic number.

28709423 is a deficient number, since it is larger than the sum of its proper divisors (685081).

28709423 is an equidigital number, since it uses as much as digits as its factorization.

28709423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15613 (or 15570 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 35.

The square root of 28709423 is about 5358.1174865805. The cubic root of 28709423 is about 306.2020928533.

The spelling of 28709423 in words is "twenty-eight million, seven hundred nine thousand, four hundred twenty-three".