28256247 has 6 divisors (see below), whose sum is σ = 40814592. Its totient is φ = 18837492.

The previous prime is 28256243. The next prime is 28256251. The reversal of 28256247 is 74265282.

28256247 is a `hidden beast` number, since 2 + 8 + 25 + 624 + 7 = 666.

It is an interprime number because it is at equal distance from previous prime (28256243) and next prime (28256251).

It is not a de Polignac number, because 28256247 - 2² = 28256243 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28256243) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1569783 + ... + 1569800.

It is an arithmetic number, because the mean of its divisors is an integer number (6802432).

Almost surely, 2^28256247 is an apocalyptic number.

28256247 is a deficient number, since it is larger than the sum of its proper divisors (12558345).

28256247 is a wasteful number, since it uses less digits than its factorization.

28256247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3139589 (or 3139586 counting only the distinct ones).

The product of its digits is 53760, while the sum is 36.

The square root of 28256247 is about 5315.6605422092. The cubic root of 28256247 is about 304.5824151851.

The spelling of 28256247 in words is "twenty-eight million, two hundred fifty-six thousand, two hundred forty-seven".