28072247 has 6 divisors (see below), whose sum is σ = 32655528. Its totient is φ = 24061884.

The previous prime is 28072241. The next prime is 28072271. The reversal of 28072247 is 74227082.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-28072247 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 (28072241) 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, 286403 + ... + 286500.

It is an arithmetic number, because the mean of its divisors is an integer number (5442588).

Almost surely, 2^28072247 is an apocalyptic number.

28072247 is a deficient number, since it is larger than the sum of its proper divisors (4583281).

28072247 is an equidigital number, since it uses as much as digits as its factorization.

28072247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 572917 (or 572910 counting only the distinct ones).

The product of its (nonzero) digits is 12544, while the sum is 32.

The square root of 28072247 is about 5298.3249239736. The cubic root of 28072247 is about 303.9198448359.

It can be divided in two parts, 280 and 72247, that added together give a palindrome (72527).

The spelling of 28072247 in words is "twenty-eight million, seventy-two thousand, two hundred forty-seven".