381808613 has 2 divisors, whose sum is σ = 381808614. Its totient is φ = 381808612.

The previous prime is 381808573. The next prime is 381808621. The reversal of 381808613 is 316808183.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 381694369 + 114244 = 19537^2 + 338^2 .

It is an emirp because it is prime and its reverse (316808183) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 381808613 - 2¹⁰ = 381807589 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (381808643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 190904306 + 190904307.

It is an arithmetic number, because the mean of its divisors is an integer number (190904307).

Almost surely, 2^381808613 is an apocalyptic number.

It is an amenable number.

381808613 is a deficient number, since it is larger than the sum of its proper divisors (1).

381808613 is an equidigital number, since it uses as much as digits as its factorization.

381808613 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27648, while the sum is 38.

The square root of 381808613 is about 19539.9235668925. The cubic root of 381808613 is about 725.4629547297.

The spelling of 381808613 in words is "three hundred eighty-one million, eight hundred eight thousand, six hundred thirteen".