102405139 has 2 divisors, whose sum is σ = 102405140. Its totient is φ = 102405138.

The previous prime is 102405137. The next prime is 102405181. The reversal of 102405139 is 931504201.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 102405139 - 2¹ = 102405137 is a prime.

Together with 102405137, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (102405133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51202569 + 51202570.

It is an arithmetic number, because the mean of its divisors is an integer number (51202570).

Almost surely, 2^102405139 is an apocalyptic number.

102405139 is a deficient number, since it is larger than the sum of its proper divisors (1).

102405139 is an equidigital number, since it uses as much as digits as its factorization.

102405139 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 102405139 is about 10119.5424303671. The cubic root of 102405139 is about 467.8506642994.

The spelling of 102405139 in words is "one hundred two million, four hundred five thousand, one hundred thirty-nine".