1831381 has 2 divisors, whose sum is σ = 1831382. Its totient is φ = 1831380.

The previous prime is 1831373. The next prime is 1831399.

1831381 is nontrivially palindromic in base 10.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1664100 + 167281 = 1290^2 + 409^2 .

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 1831381 - 2³ = 1831373 is a prime.

It is a super-2 number, since 2×1831381² = 6707912734322, which contains 22 as substring.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1831331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 915690 + 915691.

It is an arithmetic number, because the mean of its divisors is an integer number (915691).

2^1831381 is an apocalyptic number.

It is an amenable number.

1831381 is a deficient number, since it is larger than the sum of its proper divisors (1).

1831381 is an equidigital number, since it uses as much as digits as its factorization.

1831381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 576, while the sum is 25.

The square root of 1831381 is about 1353.2852618720. The cubic root of 1831381 is about 122.3468807412.

The spelling of 1831381 in words is "one million, eight hundred thirty-one thousand, three hundred eighty-one".