28706709 has 16 divisors (see below), whose sum is σ = 39693888. Its totient is φ = 18438912.

The previous prime is 28706681. The next prime is 28706729. The reversal of 28706709 is 90760782.

It is not a de Polignac number, because 28706709 - 2⁵ = 28706677 is a prime.

It is a super-2 number, since 2×28706709² = 1648150283221362, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28706729) 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 15 ways as a sum of consecutive naturals, for example, 10669 + ... + 13085.

It is an arithmetic number, because the mean of its divisors is an integer number (2480868).

Almost surely, 2^28706709 is an apocalyptic number.

It is an amenable number.

28706709 is a deficient number, since it is larger than the sum of its proper divisors (10987179).

28706709 is a wasteful number, since it uses less digits than its factorization.

28706709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2564.

The product of its (nonzero) digits is 42336, while the sum is 39.

The square root of 28706709 is about 5357.8642200041. The cubic root of 28706709 is about 306.1924437720.

The spelling of 28706709 in words is "twenty-eight million, seven hundred six thousand, seven hundred nine".