28439667 has 20 divisors (see below), whose sum is σ = 42630720. Its totient is φ = 18894384.

The previous prime is 28439659. The next prime is 28439669. The reversal of 28439667 is 76693482.

It is not a de Polignac number, because 28439667 - 2³ = 28439659 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (28439669) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 38433 + ... + 39165.

It is an arithmetic number, because the mean of its divisors is an integer number (2131536).

Almost surely, 2^28439667 is an apocalyptic number.

28439667 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

28439667 is a deficient number, since it is larger than the sum of its proper divisors (14191053).

28439667 is an equidigital number, since it uses as much as digits as its factorization.

28439667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1224 (or 1215 counting only the distinct ones).

The product of its digits is 435456, while the sum is 45.

The square root of 28439667 is about 5332.8854291087. The cubic root of 28439667 is about 305.2400403635.

The spelling of 28439667 in words is "twenty-eight million, four hundred thirty-nine thousand, six hundred sixty-seven".