5081981 has 2 divisors, whose sum is σ = 5081982. Its totient is φ = 5081980.

The previous prime is 5081959. The next prime is 5081983. The reversal of 5081981 is 1891805.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3496900 + 1585081 = 1870^2 + 1259^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-5081981 is a prime.

It is a super-2 number, since 2×5081981² = 51653061768722, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 5081983, it forms a pair of twin primes.

It is a Chen 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 (5081983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2540990 + 2540991.

It is an arithmetic number, because the mean of its divisors is an integer number (2540991).

Almost surely, 2^5081981 is an apocalyptic number.

It is an amenable number.

5081981 is a deficient number, since it is larger than the sum of its proper divisors (1).

5081981 is an equidigital number, since it uses as much as digits as its factorization.

5081981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2880, while the sum is 32.

The square root of 5081981 is about 2254.3249543932. The cubic root of 5081981 is about 171.9271031457.

The spelling of 5081981 in words is "five million, eighty-one thousand, nine hundred eighty-one".