2011381 has 2 divisors, whose sum is σ = 2011382. Its totient is φ = 2011380.

The previous prime is 2011363. The next prime is 2011391. The reversal of 2011381 is 1831102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1418481 + 592900 = 1191^2 + 770^2 .

It is a cyclic number.

It is not a de Polignac number, because 2011381 - 2¹¹ = 2009333 is a prime.

It is a super-2 number, since 2×2011381² = 8091307054322, which contains 22 as substring.

It is a plaindrome in base 13.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2011391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1005690 + 1005691.

It is an arithmetic number, because the mean of its divisors is an integer number (1005691).

2^2011381 is an apocalyptic number.

It is an amenable number.

2011381 is a deficient number, since it is larger than the sum of its proper divisors (1).

2011381 is an equidigital number, since it uses as much as digits as its factorization.

2011381 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48, while the sum is 16.

The square root of 2011381 is about 1418.2316453951. The cubic root of 2011381 is about 126.2306391250.

Adding to 2011381 its reverse (1831102), we get a palindrome (3842483).

The spelling of 2011381 in words is "two million, eleven thousand, three hundred eighty-one".