28917439 has 2 divisors, whose sum is σ = 28917440. Its totient is φ = 28917438.

The previous prime is 28917431. The next prime is 28917443. The reversal of 28917439 is 93471982.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28917439 - 2³ = 28917431 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 28917395 and 28917404.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28917431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14458719 + 14458720.

It is an arithmetic number, because the mean of its divisors is an integer number (14458720).

Almost surely, 2^28917439 is an apocalyptic number.

28917439 is a deficient number, since it is larger than the sum of its proper divisors (1).

28917439 is an equidigital number, since it uses as much as digits as its factorization.

28917439 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108864, while the sum is 43.

The square root of 28917439 is about 5377.4937470907. The cubic root of 28917439 is about 306.9398496464.

The spelling of 28917439 in words is "twenty-eight million, nine hundred seventeen thousand, four hundred thirty-nine".