28315307 has 4 divisors (see below), whose sum is σ = 29228736. Its totient is φ = 27401880.

The previous prime is 28315289. The next prime is 28315327. The reversal of 28315307 is 70351382.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28315307 - 2¹⁰ = 28314283 is a prime.

It is a super-2 number, since 2×28315307² = 1603513221008498, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28315307.

It is not an unprimeable number, because it can be changed into a prime (28315327) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 456668 + ... + 456729.

It is an arithmetic number, because the mean of its divisors is an integer number (7307184).

Almost surely, 2^28315307 is an apocalyptic number.

28315307 is a deficient number, since it is larger than the sum of its proper divisors (913429).

28315307 is an equidigital number, since it uses as much as digits as its factorization.

28315307 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 913428.

The product of its (nonzero) digits is 5040, while the sum is 29.

The square root of 28315307 is about 5321.2129256402. The cubic root of 28315307 is about 304.7944758898.

Adding to 28315307 its reverse (70351382), we get a palindrome (98666689).

The spelling of 28315307 in words is "twenty-eight million, three hundred fifteen thousand, three hundred seven".