831905381 has 2 divisors, whose sum is σ = 831905382. Its totient is φ = 831905380.

The previous prime is 831905363. The next prime is 831905383. The reversal of 831905381 is 183509138.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 433264225 + 398641156 = 20815^2 + 19966^2 .

It is a cyclic number.

It is not a de Polignac number, because 831905381 - 2²² = 827711077 is a prime.

It is a super-2 number, since 2×831905381² = 1384133125873510322, which contains 22 as substring.

Together with 831905383, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (831905383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 415952690 + 415952691.

It is an arithmetic number, because the mean of its divisors is an integer number (415952691).

Almost surely, 2^831905381 is an apocalyptic number.

It is an amenable number.

831905381 is a deficient number, since it is larger than the sum of its proper divisors (1).

831905381 is an equidigital number, since it uses as much as digits as its factorization.

831905381 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 25920, while the sum is 38.

The square root of 831905381 is about 28842.7699952692. The cubic root of 831905381 is about 940.4982197404.

The spelling of 831905381 in words is "eight hundred thirty-one million, nine hundred five thousand, three hundred eighty-one".