7105643981 has 2 divisors, whose sum is σ = 7105643982. Its totient is φ = 7105643980.

The previous prime is 7105643957. The next prime is 7105643983. The reversal of 7105643981 is 1893465017.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6382571881 + 723072100 = 79891^2 + 26890^2 .

It is a cyclic number.

It is not a de Polignac number, because 7105643981 - 2²⁶ = 7038535117 is a prime.

It is a super-2 number, since 2×7105643981² (a number of 21 digits) contains 22 as substring.

Together with 7105643983, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7105643983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3552821990 + 3552821991.

It is an arithmetic number, because the mean of its divisors is an integer number (3552821991).

Almost surely, 2^7105643981 is an apocalyptic number.

It is an amenable number.

7105643981 is a deficient number, since it is larger than the sum of its proper divisors (1).

7105643981 is an equidigital number, since it uses as much as digits as its factorization.

7105643981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 181440, while the sum is 44.

The square root of 7105643981 is about 84294.9819443601. The cubic root of 7105643981 is about 1922.5064903509.

The spelling of 7105643981 in words is "seven billion, one hundred five million, six hundred forty-three thousand, nine hundred eighty-one".