28307091 has 8 divisors (see below), whose sum is σ = 39963024. Its totient is φ = 17761280.

The previous prime is 28307087. The next prime is 28307101. The reversal of 28307091 is 19070382.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28307091 - 2² = 28307087 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28307011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 277470 + ... + 277571.

It is an arithmetic number, because the mean of its divisors is an integer number (4995378).

Almost surely, 2^28307091 is an apocalyptic number.

28307091 is a deficient number, since it is larger than the sum of its proper divisors (11655933).

28307091 is a wasteful number, since it uses less digits than its factorization.

28307091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 555061.

The product of its (nonzero) digits is 3024, while the sum is 30.

The square root of 28307091 is about 5320.4408651915. The cubic root of 28307091 is about 304.7649932068.

The spelling of 28307091 in words is "twenty-eight million, three hundred seven thousand, ninety-one".