102806489 has 2 divisors, whose sum is σ = 102806490. Its totient is φ = 102806488.

The previous prime is 102806467. The next prime is 102806491. The reversal of 102806489 is 984608201.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 86806489 + 16000000 = 9317^2 + 4000^2 .

It is an emirp because it is prime and its reverse (984608201) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 102806489 - 2⁸ = 102806233 is a prime.

Together with 102806491, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (102806449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51403244 + 51403245.

It is an arithmetic number, because the mean of its divisors is an integer number (51403245).

Almost surely, 2^102806489 is an apocalyptic number.

It is an amenable number.

102806489 is a deficient number, since it is larger than the sum of its proper divisors (1).

102806489 is an equidigital number, since it uses as much as digits as its factorization.

102806489 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27648, while the sum is 38.

The square root of 102806489 is about 10139.3534803754. The cubic root of 102806489 is about 468.4610734097.

The spelling of 102806489 in words is "one hundred two million, eight hundred six thousand, four hundred eighty-nine".