102685909 has 2 divisors, whose sum is σ = 102685910. Its totient is φ = 102685908.

The previous prime is 102685903. The next prime is 102685927. The reversal of 102685909 is 909586201.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 88078225 + 14607684 = 9385^2 + 3822^2 .

It is a cyclic number.

It is not a de Polignac number, because 102685909 - 2¹⁹ = 102161621 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (102685903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51342954 + 51342955.

It is an arithmetic number, because the mean of its divisors is an integer number (51342955).

Almost surely, 2^102685909 is an apocalyptic number.

It is an amenable number.

102685909 is a deficient number, since it is larger than the sum of its proper divisors (1).

102685909 is an equidigital number, since it uses as much as digits as its factorization.

102685909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 38880, while the sum is 40.

The square root of 102685909 is about 10133.4055973301. The cubic root of 102685909 is about 468.2778517233.

The spelling of 102685909 in words is "one hundred two million, six hundred eighty-five thousand, nine hundred nine".