28878251 has 2 divisors, whose sum is σ = 28878252. Its totient is φ = 28878250.

The previous prime is 28878217. The next prime is 28878281. The reversal of 28878251 is 15287882.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28878251 - 2¹⁴ = 28861867 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 28878199 and 28878208.

It is not a weakly prime, because it can be changed into another prime (28878281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14439125 + 14439126.

It is an arithmetic number, because the mean of its divisors is an integer number (14439126).

Almost surely, 2^28878251 is an apocalyptic number.

28878251 is a deficient number, since it is larger than the sum of its proper divisors (1).

28878251 is an equidigital number, since it uses as much as digits as its factorization.

28878251 is an evil number, because the sum of its binary digits is even.

The product of its digits is 71680, while the sum is 41.

The square root of 28878251 is about 5373.8488069539. The cubic root of 28878251 is about 306.8011352372.

The spelling of 28878251 in words is "twenty-eight million, eight hundred seventy-eight thousand, two hundred fifty-one".