28756247 has 8 divisors (see below), whose sum is σ = 31011120. Its totient is φ = 26507520.

The previous prime is 28756243. The next prime is 28756267. The reversal of 28756247 is 74265782.

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

It is not a de Polignac number, because 28756247 - 2² = 28756243 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28756243) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14279 + ... + 16167.

It is an arithmetic number, because the mean of its divisors is an integer number (3876390).

Almost surely, 2^28756247 is an apocalyptic number.

28756247 is a deficient number, since it is larger than the sum of its proper divisors (2254873).

28756247 is a wasteful number, since it uses less digits than its factorization.

28756247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3073.

The product of its digits is 188160, while the sum is 41.

The square root of 28756247 is about 5362.4851514946. The cubic root of 28756247 is about 306.3684705051.

The spelling of 28756247 in words is "twenty-eight million, seven hundred fifty-six thousand, two hundred forty-seven".