13785813 has 12 divisors (see below), whose sum is σ = 19945068. Its totient is φ = 9175680.

The previous prime is 13785803. The next prime is 13785823. The reversal of 13785813 is 31858731.

13785813 is a `hidden beast` number, since 1 + 3 + 78 + 581 + 3 = 666.

It is an interprime number because it is at equal distance from previous prime (13785803) and next prime (13785823).

It can be written as a sum of positive squares in 2 ways, for example, as 13373649 + 412164 = 3657^2 + 642^2 .

It is not a de Polignac number, because 13785813 - 2⁵ = 13785781 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13785803) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9981 + ... + 11277.

It is an arithmetic number, because the mean of its divisors is an integer number (1662089).

Almost surely, 2^13785813 is an apocalyptic number.

It is an amenable number.

13785813 is a deficient number, since it is larger than the sum of its proper divisors (6159255).

13785813 is a wasteful number, since it uses less digits than its factorization.

13785813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2484 (or 2481 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 13785813 is about 3712.9251271740. The cubic root of 13785813 is about 239.7788066188.

The spelling of 13785813 in words is "thirteen million, seven hundred eighty-five thousand, eight hundred thirteen".