2231381 has 2 divisors, whose sum is σ = 2231382. Its totient is φ = 2231380.

The previous prime is 2231371. The next prime is 2231389. The reversal of 2231381 is 1831322.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2102500 + 128881 = 1450^2 + 359^2 .

It is a cyclic number.

It is not a de Polignac number, because 2231381 - 2¹⁴ = 2214997 is a prime.

It is a super-3 number, since 3×2231381³ = 33330547458722638023, which contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2231389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1115690 + 1115691.

It is an arithmetic number, because the mean of its divisors is an integer number (1115691).

2^2231381 is an apocalyptic number.

It is an amenable number.

2231381 is a deficient number, since it is larger than the sum of its proper divisors (1).

2231381 is an equidigital number, since it uses as much as digits as its factorization.

2231381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 288, while the sum is 20.

The square root of 2231381 is about 1493.7807737416. The cubic root of 2231381 is about 130.6746193214.

The spelling of 2231381 in words is "two million, two hundred thirty-one thousand, three hundred eighty-one".