5663311981 has 2 divisors, whose sum is σ = 5663311982. Its totient is φ = 5663311980.

The previous prime is 5663311963. The next prime is 5663311999. The reversal of 5663311981 is 1891133665.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (5663311963) and next prime (5663311999).

It can be written as a sum of positive squares in only one way, i.e., 5660305225 + 3006756 = 75235^2 + 1734^2 .

It is a cyclic number.

It is not a de Polignac number, because 5663311981 - 2⁷ = 5663311853 is a prime.

It is a super-2 number, since 2×5663311981² = 64146205188276288722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (5663311481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2831655990 + 2831655991.

It is an arithmetic number, because the mean of its divisors is an integer number (2831655991).

Almost surely, 2^5663311981 is an apocalyptic number.

It is an amenable number.

5663311981 is a deficient number, since it is larger than the sum of its proper divisors (1).

5663311981 is an equidigital number, since it uses as much as digits as its factorization.

5663311981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 116640, while the sum is 43.

The square root of 5663311981 is about 75254.9797754275. The cubic root of 5663311981 is about 1782.4751977623.

The spelling of 5663311981 in words is "five billion, six hundred sixty-three million, three hundred eleven thousand, nine hundred eighty-one".