2331781 has 2 divisors, whose sum is σ = 2331782. Its totient is φ = 2331780.

The previous prime is 2331779. The next prime is 2331829. The reversal of 2331781 is 1871332.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1934881 + 396900 = 1391^2 + 630^2 .

It is a cyclic number.

It is not a de Polignac number, because 2331781 - 2¹ = 2331779 is a prime.

It is a super-2 number, since 2×2331781² = 10874405263922, which contains 22 as substring.

Together with 2331779, it forms a pair of twin primes.

It is a plaindrome in base 14.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2331751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1165890 + 1165891.

It is an arithmetic number, because the mean of its divisors is an integer number (1165891).

2^2331781 is an apocalyptic number.

It is an amenable number.

2331781 is a deficient number, since it is larger than the sum of its proper divisors (1).

2331781 is an equidigital number, since it uses as much as digits as its factorization.

2331781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1008, while the sum is 25.

The square root of 2331781 is about 1527.0170267551. The cubic root of 2331781 is about 132.6058202945.

The spelling of 2331781 in words is "two million, three hundred thirty-one thousand, seven hundred eighty-one".