381911831 has 6 divisors (see below), whose sum is σ = 444264840. Its totient is φ = 327352956.

The previous prime is 381911821. The next prime is 381911867. The reversal of 381911831 is 138119183.

It is not a de Polignac number, because 381911831 - 2¹⁴ = 381895447 is a prime.

It is a super-2 number, since 2×381911831² = 291713293315545122, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 381911791 and 381911800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (381911821) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3897011 + ... + 3897108.

It is an arithmetic number, because the mean of its divisors is an integer number (74044140).

Almost surely, 2^381911831 is an apocalyptic number.

381911831 is a deficient number, since it is larger than the sum of its proper divisors (62353009).

381911831 is an equidigital number, since it uses as much as digits as its factorization.

381911831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7794133 (or 7794126 counting only the distinct ones).

The product of its digits is 5184, while the sum is 35.

The square root of 381911831 is about 19542.5645962857. The cubic root of 381911831 is about 725.5283226356.

The spelling of 381911831 in words is "three hundred eighty-one million, nine hundred eleven thousand, eight hundred thirty-one".