28978867 has 2 divisors, whose sum is σ = 28978868. Its totient is φ = 28978866.

The previous prime is 28978823. The next prime is 28978889. The reversal of 28978867 is 76887982.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28978867 - 2⁷ = 28978739 is a prime.

It is not a weakly prime, because it can be changed into another prime (28978567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14489433 + 14489434.

It is an arithmetic number, because the mean of its divisors is an integer number (14489434).

Almost surely, 2^28978867 is an apocalyptic number.

28978867 is a deficient number, since it is larger than the sum of its proper divisors (1).

28978867 is an equidigital number, since it uses as much as digits as its factorization.

28978867 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2709504, while the sum is 55.

The square root of 28978867 is about 5383.2022997469. The cubic root of 28978867 is about 307.1570353856.

It can be divided in two parts, 289788 and 67, that multiplied together give a triangular number (19415796 = T₆₂₃₁).

The spelling of 28978867 in words is "twenty-eight million, nine hundred seventy-eight thousand, eight hundred sixty-seven".