28709340 has 48 divisors (see below), whose sum is σ = 87696000. Its totient is φ = 6959680.

The previous prime is 28709327. The next prime is 28709357. The reversal of 28709340 is 4390782.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 21090 + ... + 22409.

It is an arithmetic number, because the mean of its divisors is an integer number (1827000).

Almost surely, 2^28709340 is an apocalyptic number.

28709340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28709340 is an abundant number, since it is smaller than the sum of its proper divisors (58986660).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28709340 is a wasteful number, since it uses less digits than its factorization.

28709340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43522 (or 43520 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 33.

The square root of 28709340 is about 5358.1097413174. The cubic root of 28709340 is about 306.2017977725.

The spelling of 28709340 in words is "twenty-eight million, seven hundred nine thousand, three hundred forty".