381893881 has 2 divisors, whose sum is σ = 381893882. Its totient is φ = 381893880.

The previous prime is 381893861. The next prime is 381893887. The reversal of 381893881 is 188398183.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 365765625 + 16128256 = 19125^2 + 4016^2 .

It is an emirp because it is prime and its reverse (188398183) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 381893881 - 2²⁵ = 348339449 is a prime.

It is a super-2 number, since 2×381893881² = 291685872690484322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (381893887) 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, 190946940 + 190946941.

It is an arithmetic number, because the mean of its divisors is an integer number (190946941).

Almost surely, 2^381893881 is an apocalyptic number.

It is an amenable number.

381893881 is a deficient number, since it is larger than the sum of its proper divisors (1).

381893881 is an equidigital number, since it uses as much as digits as its factorization.

381893881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 331776, while the sum is 49.

The square root of 381893881 is about 19542.1053369385. The cubic root of 381893881 is about 725.5169557560.

The spelling of 381893881 in words is "three hundred eighty-one million, eight hundred ninety-three thousand, eight hundred eighty-one".