2163881 has 2 divisors, whose sum is σ = 2163882. Its totient is φ = 2163880.

The previous prime is 2163869. The next prime is 2163883. The reversal of 2163881 is 1883612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1651225 + 512656 = 1285^2 + 716^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2163881 is a prime.

It is a super-2 number, since 2×2163881² = 9364761964322, which contains 22 as substring.

Together with 2163883, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (2163883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1081940 + 1081941.

It is an arithmetic number, because the mean of its divisors is an integer number (1081941).

2^2163881 is an apocalyptic number.

It is an amenable number.

2163881 is a deficient number, since it is larger than the sum of its proper divisors (1).

2163881 is an equidigital number, since it uses as much as digits as its factorization.

2163881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2304, while the sum is 29.

The square root of 2163881 is about 1471.0135961302. The cubic root of 2163881 is about 129.3434550893.

The spelling of 2163881 in words is "two million, one hundred sixty-three thousand, eight hundred eighty-one".