2217631982981 has 2 divisors, whose sum is σ = 2217631982982. Its totient is φ = 2217631982980.

The previous prime is 2217631982947. The next prime is 2217631982983. The reversal of 2217631982981 is 1892891367122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2026041938881 + 191590044100 = 1423391^2 + 437710^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2217631982981 is a prime.

It is a super-2 number, since 2×2217631982981² (a number of 25 digits) contains 22 as substring.

Together with 2217631982983, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2217631982981.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2217631982983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1108815991490 + 1108815991491.

It is an arithmetic number, because the mean of its divisors is an integer number (1108815991491).

Almost surely, 2^{2217631982981} is an apocalyptic number.

It is an amenable number.

2217631982981 is a deficient number, since it is larger than the sum of its proper divisors (1).

2217631982981 is an equidigital number, since it uses as much as digits as its factorization.

2217631982981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5225472, while the sum is 59.

The spelling of 2217631982981 in words is "two trillion, two hundred seventeen billion, six hundred thirty-one million, nine hundred eighty-two thousand, nine hundred eighty-one".