1180909661 has 2 divisors, whose sum is σ = 1180909662. Its totient is φ = 1180909660.

The previous prime is 1180909637. The next prime is 1180909663. The reversal of 1180909661 is 1669090811.

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., 1142034436 + 38875225 = 33794^2 + 6235^2 .

It is an emirp because it is prime and its reverse (1669090811) is a distict prime. It is also a bemirp because it and its reverse can be mirrored producing other two distinct primes, 1996060811 and 1180606991.

It is a cyclic number.

It is not a de Polignac number, because 1180909661 - 2¹⁴ = 1180893277 is a prime.

It is a Sophie Germain prime.

Together with 1180909663, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1180909663) 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, 590454830 + 590454831.

It is an arithmetic number, because the mean of its divisors is an integer number (590454831).

Almost surely, 2^1180909661 is an apocalyptic number.

It is an amenable number.

1180909661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1180909661 is an equidigital number, since it uses as much as digits as its factorization.

1180909661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23328, while the sum is 41.

The square root of 1180909661 is about 34364.3661515821. The cubic root of 1180909661 is about 1056.9932774928.

The spelling of 1180909661 in words is "one billion, one hundred eighty million, nine hundred nine thousand, six hundred sixty-one".