28431268 has 6 divisors (see below), whose sum is σ = 49754726. Its totient is φ = 14215632.

The previous prime is 28431257. The next prime is 28431269. The reversal of 28431268 is 86213482.

It can be written as a sum of positive squares in only one way, i.e., 28323684 + 107584 = 5322^2 + 328^2 .

It is not an unprimeable number, because it can be changed into a prime (28431269) 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 as a sum of consecutive naturals, namely, 3553905 + ... + 3553912.

Almost surely, 2^28431268 is an apocalyptic number.

It is an amenable number.

28431268 is a deficient number, since it is larger than the sum of its proper divisors (21323458).

28431268 is a wasteful number, since it uses less digits than its factorization.

28431268 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7107821 (or 7107819 counting only the distinct ones).

The product of its digits is 18432, while the sum is 34.

The square root of 28431268 is about 5332.0978985761. The cubic root of 28431268 is about 305.2099888686.

The spelling of 28431268 in words is "twenty-eight million, four hundred thirty-one thousand, two hundred sixty-eight".