28432507 has 4 divisors (see below), whose sum is σ = 28537696. Its totient is φ = 28327320.

The previous prime is 28432501. The next prime is 28432511. The reversal of 28432507 is 70523482.

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 28432507 - 2¹⁵ = 28399739 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28432501) 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, 52188 + ... + 52729.

It is an arithmetic number, because the mean of its divisors is an integer number (7134424).

Almost surely, 2^28432507 is an apocalyptic number.

28432507 is a deficient number, since it is larger than the sum of its proper divisors (105189).

28432507 is a wasteful number, since it uses less digits than its factorization.

28432507 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105188.

The product of its (nonzero) digits is 13440, while the sum is 31.

The square root of 28432507 is about 5332.2140804735. The cubic root of 28432507 is about 305.2144223640.

Adding to 28432507 its reverse (70523482), we get a palindrome (98955989).

The spelling of 28432507 in words is "twenty-eight million, four hundred thirty-two thousand, five hundred seven".