185137013209 has 2 divisors, whose sum is σ = 185137013210. Its totient is φ = 185137013208.

The previous prime is 185137013207. The next prime is 185137013249. The reversal of 185137013209 is 902310731581.

It is an a-pointer prime, because the next prime (185137013249) can be obtained adding 185137013209 to its sum of digits (40).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 171274305609 + 13862707600 = 413853^2 + 117740^2 .

It is a cyclic number.

It is not a de Polignac number, because 185137013209 - 2¹ = 185137013207 is a prime.

Together with 185137013207, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (185137013207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 92568506604 + 92568506605.

It is an arithmetic number, because the mean of its divisors is an integer number (92568506605).

Almost surely, 2^185137013209 is an apocalyptic number.

It is an amenable number.

185137013209 is a deficient number, since it is larger than the sum of its proper divisors (1).

185137013209 is an equidigital number, since it uses as much as digits as its factorization.

185137013209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 45360, while the sum is 40.

The spelling of 185137013209 in words is "one hundred eighty-five billion, one hundred thirty-seven million, thirteen thousand, two hundred nine".