185866138349 has 2 divisors, whose sum is σ = 185866138350. Its totient is φ = 185866138348.

The previous prime is 185866138333. The next prime is 185866138351. The reversal of 185866138349 is 943831668581.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 148479208900 + 37386929449 = 385330^2 + 193357^2 .

It is an emirp because it is prime and its reverse (943831668581) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 185866138349 - 2⁴ = 185866138333 is a prime.

Together with 185866138351, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 185866138291 and 185866138300.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (185866138399) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 92933069174 + 92933069175.

It is an arithmetic number, because the mean of its divisors is an integer number (92933069175).

Almost surely, 2^185866138349 is an apocalyptic number.

It is an amenable number.

185866138349 is a deficient number, since it is larger than the sum of its proper divisors (1).

185866138349 is an equidigital number, since it uses as much as digits as its factorization.

185866138349 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 29859840, while the sum is 62.

The spelling of 185866138349 in words is "one hundred eighty-five billion, eight hundred sixty-six million, one hundred thirty-eight thousand, three hundred forty-nine".