1813685173 has 2 divisors, whose sum is σ = 1813685174. Its totient is φ = 1813685172.

The previous prime is 1813685161. The next prime is 1813685177. The reversal of 1813685173 is 3715863181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1281783204 + 531901969 = 35802^2 + 23063^2 .

It is a cyclic number.

It is not a de Polignac number, because 1813685173 - 2²¹ = 1811588021 is a prime.

It is a super-3 number, since 3×1813685173³ (a number of 29 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1813685177) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 906842586 + 906842587.

It is an arithmetic number, because the mean of its divisors is an integer number (906842587).

Almost surely, 2^1813685173 is an apocalyptic number.

It is an amenable number.

1813685173 is a deficient number, since it is larger than the sum of its proper divisors (1).

1813685173 is an equidigital number, since it uses as much as digits as its factorization.

1813685173 is an evil number, because the sum of its binary digits is even.

The product of its digits is 120960, while the sum is 43.

The square root of 1813685173 is about 42587.3827911507. The cubic root of 1813685173 is about 1219.5154335144.

The spelling of 1813685173 in words is "one billion, eight hundred thirteen million, six hundred eighty-five thousand, one hundred seventy-three".