28743309 has 16 divisors (see below), whose sum is σ = 48666240. Its totient is φ = 16424640.

The previous prime is 28743289. The next prime is 28743313. The reversal of 28743309 is 90334782.

It is not a de Polignac number, because 28743309 - 2¹¹ = 28741261 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28743329) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 75852 + ... + 76229.

It is an arithmetic number, because the mean of its divisors is an integer number (3041640).

Almost surely, 2^28743309 is an apocalyptic number.

It is an amenable number.

28743309 is a deficient number, since it is larger than the sum of its proper divisors (19922931).

28743309 is a wasteful number, since it uses less digits than its factorization.

28743309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152097 (or 152091 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 36.

The square root of 28743309 is about 5361.2786721080. The cubic root of 28743309 is about 306.3225165496.

The spelling of 28743309 in words is "twenty-eight million, seven hundred forty-three thousand, three hundred nine".