6998995561 has 2 divisors, whose sum is σ = 6998995562. Its totient is φ = 6998995560.

The previous prime is 6998995547. The next prime is 6998995631. The reversal of 6998995561 is 1655998996.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6586296336 + 412699225 = 81156^2 + 20315^2 .

It is a cyclic number.

It is not a de Polignac number, because 6998995561 - 2⁵ = 6998995529 is a prime.

It is not a weakly prime, because it can be changed into another prime (6998995361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3499497780 + 3499497781.

It is an arithmetic number, because the mean of its divisors is an integer number (3499497781).

Almost surely, 2^6998995561 is an apocalyptic number.

It is an amenable number.

6998995561 is a deficient number, since it is larger than the sum of its proper divisors (1).

6998995561 is an equidigital number, since it uses as much as digits as its factorization.

6998995561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 47239200, while the sum is 67.

The square root of 6998995561 is about 83659.9997669137. Note that the first 3 decimals coincide. The cubic root of 6998995561 is about 1912.8396820774.

The spelling of 6998995561 in words is "six billion, nine hundred ninety-eight million, nine hundred ninety-five thousand, five hundred sixty-one".