2689120661 has 2 divisors, whose sum is σ = 2689120662. Its totient is φ = 2689120660.

The previous prime is 2689120633. The next prime is 2689120663. The reversal of 2689120661 is 1660219862.

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., 2672269636 + 16851025 = 51694^2 + 4105^2 .

It is a cyclic number.

It is not a de Polignac number, because 2689120661 - 2¹⁴ = 2689104277 is a prime.

Together with 2689120663, 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 (2689120663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1344560330 + 1344560331.

It is an arithmetic number, because the mean of its divisors is an integer number (1344560331).

Almost surely, 2^2689120661 is an apocalyptic number.

It is an amenable number.

2689120661 is a deficient number, since it is larger than the sum of its proper divisors (1).

2689120661 is an equidigital number, since it uses as much as digits as its factorization.

2689120661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 62208, while the sum is 41.

The square root of 2689120661 is about 51856.7320701951. The cubic root of 2689120661 is about 1390.6038576702.

The spelling of 2689120661 in words is "two billion, six hundred eighty-nine million, one hundred twenty thousand, six hundred sixty-one".