28968139 has 2 divisors, whose sum is σ = 28968140. Its totient is φ = 28968138.

The previous prime is 28968101. The next prime is 28968143. The reversal of 28968139 is 93186982.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28968139 - 2¹³ = 28959947 is a prime.

It is not a weakly prime, because it can be changed into another prime (28968169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14484069 + 14484070.

It is an arithmetic number, because the mean of its divisors is an integer number (14484070).

Almost surely, 2^28968139 is an apocalyptic number.

28968139 is a deficient number, since it is larger than the sum of its proper divisors (1).

28968139 is an equidigital number, since it uses as much as digits as its factorization.

28968139 is an evil number, because the sum of its binary digits is even.

The product of its digits is 186624, while the sum is 46.

The square root of 28968139 is about 5382.2057745872. The cubic root of 28968139 is about 307.1191274464.

The spelling of 28968139 in words is "twenty-eight million, nine hundred sixty-eight thousand, one hundred thirty-nine".